医学生理学 英文影印版PDF电子书下载

UNIT Ⅰ Introduction to Physiology: The Cell and General Physiology 2

CHAPTER 1 Functional Organization of the Human Body and Control of the Internal Environment 2

Cells as the Living Units of the Body 2

Extracellular Fluid—The Internal Environment 2

Homeostatic Mechanisms of the Major Functional Systems 3

Homeostasis 3

Extracellular Fluid Transport System—The Circulatory System 3

Origin of Nutrients in the Extracellular Fluid 3

Control Systems of the Body 4

Reproduction 4

Regulation of Body Functions 4

Removal of Metabolic End Products 4

Examples of Control Mechanisms 5

Characteristics of Control Systems 6

Summary—Automaticity of the Body 7

CHAPTER 2 The Cell and Its Function 9

Organization of the Cell 9

Physical Structure of the Cell 10

Membranous Structures of the Cell 10

Cytoplasm and Its Organelles 12

Nucleus 14

Nucleoli and Formation of Ribosomes 15

Comparison of the Animal Cell with Precellular Forms of Life 15

Nuclear Membrane 15

Functional Systems of the Cell 16

Ingestion by the Cell—Endocytosis 16

Digestion of Pinocytic and Phagocytic Foreign Substances in the Cell—Function of the Lysosomes 17

Synthesis and Formation of Cellular Structures by the Endoplasmic Reticulum and the Golgi Apparatus 18

Extraction of Energy from Nutrients—Function of the Mitochondria 19

Locomotion of Cells 21

CHAPTER 3 Genetic Control of Protein Synthesis, Cell Function, and Cell Reproduction 24

The Genes 24

Genetic Code 25

The DNA Code Is Transferred to an RNA Code—The Process of Transcription 25

Synthesis of RNA 26

Assembly of the RNA Molecule from Activated Nucleotides Using the DNA Strand as a Template—The Process of Transcription 27

Messenger RNA—The Codons 27

Transfer RNA—The Anticodons 27

Ribosomal RNA 28

Formation of Proteins on the Ribosomes—The Process of Translation 29

Synthesis of Other Substances in the Cell 30

Control of Genetic Function and Biochemical Activity in Cells 30

Genetic Regulation 30

Control of Intracellular Function by Enzyme Regulation 32

The DNA-Genetic System Also Controls Cell Reproduction 32

Cell Reproduction Begins with Replication of the DNA 33

Cell Mitosis 34

Chromosomes and Their Replication 34

Control of Cell Growth and Cell Reproduction 35

Cell Differentiation 35

Cancer 36

UNIT Ⅱ Membrane Physiology, Nerve, and Muscle 40

CHAPTER 4 Transport of Substances Through the Cell Membrane 40

The Lipid Barrier of the Cell Membrane and Cell Membrane Transport Proteins 40

Diffusion 40

Diffusion Through the Cell Membrane 41

Diffusion Through Protein Channels and Gating of These Channels 42

Facilitated Diffusion 43

Factors That Affect Net Rate of Diffusion 44

Osmosis Across Selectively Permeable Membranes— Net Diffusion of Water 45

Active Transport 47

Primary Active Transport 47

Secondary Active Transport—Co-transport and Counter-transport 49

Active Transport Through Cellular Sheets 49

CHAPTER 5 Membrane Potentials and Action Potentials 52

Basic Physics of Membrane Potentials 52

Membrane Potentials Caused by Diffusion 52

Measuring the Membrane Potential 53

Resting Membrane Potential of Nerves 54

Origin of the Normal Resting Membrane Potential 54

Nerve Action Potential 55

Voltage-Gated Sodium and Potassium Channels 56

Summary of the Events That Cause the Action Potential 58

Roles of Other Ions During the Action Potential 59

Initiation of the Action Potential 59

Propagation of the Action Potential 59

Re-establishing Sodium and Potassium Ionic Gradients After Action Potentials Are Completed—Importance of Energy Metabolism 60

Plateau in Some Action Potentials 61

Rhythmicity of Some Excitable Tissues—Repetitive Discharge 61

Special Aspects of Signal Transmission in Nerve Trunks 62

Excitation—The Process of Eliciting the Action Potential 63

Recording Membrane Potentials and Action Potentials 64

Refractory Period After an Action Potential During Which a New Stimulus Can not Be Elicited 64

Inhibition of Excitability— Stabilizers and Local Anesthetics 64

CHAPTER 6 Contraction of Skeletal Muscle 67

Physiologic Anatomy of Skeletal Muscle 67

The Skeletal Muscle Fiber 67

General Mechanism of Muscle Contraction 68

Molecular Mechanism of Muscle Contraction 70

Molecular Characteristics of the Contractile Filaments 70

Efeet of Actin and Myosin Filament Overlap on Tension Developed by the Contracting Muscle 72

Relation of Velocity of Contraction to Load 73

Characteristics of Whole Muscle Contraction 74

Sources of Energy for Muscle Contraction 74

Work Output During Muscle Contraction 74

Energetics of Muscle Contraction 74

Mechanics of Skeletal Muscle Contraction 76

Remodeling of Muscle to Match Function 77

Rigor Mortis 78

CHAPTER 7 Excitation of Skeletal Muscle: A. Neuromuscular Transmission and B. Excitation-Contraction Coupling 80

Transmission of Impulses from Nerves to Skeletal Muscle Fibers: The Neuromuscular Junction 80

Secretion by Acetylcholine by the Nerve Terminals 80

Molecular Biology of Acetylcholine Formation and Release 82

Muscle Action Potential 83

Myasthenia Gravis 83

Drugs That Affect Transmission at the Neuromuscular Junction 83

Spread of the Action Potential to the Interior of the Muscle Fiber by Way of a Transverse Tubule System 84

Excitation-Contraction Coupling 84

Transverse Tubule—Sarcoplasmic Reticulum System 84

Release of Calcium Ions by the Sarcoplasmic Reticulum 85

CHAPTER 8 Contraction and Excitation of Smooth Muscle 87

Contraction of Smooth Muscle 87

Types of Smooth Muscle 87

Contractile Mechanism in Smooth Muscle 87

Regulation of Contraction by Calcium Ions 89

Neuromuscular Junctions of Smooth Muscle 90

Membrane Potentials and Action Potentials in Smooth Muscle 90

Neural and Hormonal Control of Smooth Muscle Contraction 90

Effect of Local Tissue Factors and Hormones to Cause Smooth Muscle Contraction Without Action Potentials 92

Source of Calcium Ions That Cause Contraction:(1)Through the Cell Membrane and (2)from the Sarcoplasmic Reticulum 93

UNIT Ⅲ The Heart 96

CHAPTER 9 Heart Muscle; The Heart as a Pump 96

Physiology of Cardiac Muscle 96

Physiologic Anatomy of Cardiac Muscle 96

Action Potentials in Cardiac Muscle 97

The Cardiac Cycle 99

Diastole and Systole 99

Function of the Ventricles as Pumps 100

Emptying of the Ventricles During Systole 100

Function of the Atria as Primer Pumps 100

Relationship of the Electrocardiogram to the Cardiac Cycle 100

Function of the Valves 101

The Aortic Pressure Curve 101

Relationship of the Heart Sounds to Heart Pumping 102

Work Output of the Heart 102

Chemical Energy Required for Cardiac Contraction: Oxygen Utilization by the Heart 103

Regulation of Heart Pumping 103

Intrinsic Regulation of Heart Pumping—The Frank-Starling Mechanism 103

Effect of Potassium and Calcium Ions on Heart Function 106

Effect of Temperature on Heart Function 106

Sinus Node (Sinoatrial Node) 107

Specialized Excitatory and Conductive System of the Heart 107

CHAPTER 10 Rhythmical Excitation of the Heart 107

Internodal Pathways and Transmission of the Cardiac Impulse Through the Atria 109

Atrioventricular Node, and Delay of Impulse Conduction from the Atria to the Ventricles 109

Rapid Transmission in the Ventricular Purkinje System 109

Transmission of the Cardiac Impulse in the Ventricular Muscle 110

Summary of the Spread of the Cardiac Impulse Through the Heart 110

Control of Excitation and Conduction in the Heart 111

The Sinus Node as the Pacemaker of the Heart 111

Role of the Purkinje System in Causing Synchronous Contraction of the Ventricular Muscle 111

Control of Heart Rhythmicity and Impulse Conduction by the Cardiac Nerves: The Sympathetic and Parasympathetic Nerves 112

Depolarization Waves Versus Repolarization Waves 114

Characteristics of the Normal Electrocardiogram 114

CHAPTER 11 The Normal Electrocardiogram 114

Relationship of Atrial and Ventricular Contraction to the Waves of the Electrocardiogram 115

Voltage and Time Calibration of the Electrocardiogram 115

Methods for Recording Electrocardiograms 116

Pen Recorder 116

Flow of Current Around the Heart During the Cardiac Cycle 116

Recording Electrical Potentials from a Partially Depolarized Mass of Syncytial Cardiac Muscle 116

Flow of Electrical Currents in the Chest Around the Heart 116

Electrocardiographic Leads 117

Three Bipolar Limb Leads 117

Chest Leads (Precordial Leads) 118

Augumented Unipolar Limb Leads 119

Principles of Vectorial Analysis of Electrocardiograms 120

Use of Vectors to Represent Electrical Potentials 120

Denoting the Direction of a Vector in Terms of Degrees 120

Axis of Each of the Standard Bipolar Leads and for Each Unipolar Limb Lead 120

CHAPTER 12 Electrocardiographic Interpretation of Cardiac Muscle and Coronary Blood Flow Abnormalities: Vectorial Analysis 120

Vectorial Analysis of Potentials Recorded in Different Leads 121

Vectorial Analysis of the Normal Electrocardiogram 122

Vectors That Occur at Successive Intervals During Depolarization of the Ventricles—The QRS Complex 122

Electrocardiogram During Repolarization—The T Wave 123

Depolarization of the Atria—The P Wave 124

Vectorcardiogram 124

Abnormal Ventricular Conditions That Cause Axis Deviation 125

Mean Electrical Axis of the Ventricular QRS—And Its Significance 125

Determining the Electrical Axis from Standard Lead Electrocardiograms 125

Conditions That Cause Abnormal Voltages of the QRS Complex 127

Increased Voltage in the Standard Bipolar Limb Leads 127

Decreased Voltage of the Electrocardiogram 127

Prolonged and Bizarre Patterns of the QRS Complex 128

Prolonged QRS Complex as a Result of Cardiac Hypertrophy or Dilatation 128

Prolonged QRS Complex Resulting from Purkinje System Blocks 128

Conditions That Cause Bizarre QRS Complexes 128

Current of Injury 128

Effect of Current of Injury on the QRS Complex 128

The J Point—The Zero Reference Potential for Analyzing Current of Injury 129

Coronary Ischemia as a Cause of Current of Injury 130

Abnormalities in the T Wave 132

Effect of Slow Conduction of the Depolarization Wave on the Characteristics of the T Wave 132

Prolonged Depolarization in Portions of the Ventricular Muscle as a Cause of Abnormalities in the T Wave 132

CHAPTER 13 Cardiac Arrhythmias and Their Electrocardiographic Interpretation 134

Abnormal Sinus Rhythms 134

Tachycardia 134

Bradycardia 134

Sinus Arrhythmia 134

Atrioventricular Block 135

Sinoatrial Block 135

Abnormal Rhythms That Result from Impulse Conduction Block 135

Incomplete Intraventricular Block—Electrical Alternans 136

Premature Contractions 136

Premature Atrial Contractions 137

A-V Nodal or A-V Bundle Premature Contractions 137

Premature Ventricular Contractions 137

Paroxysmal Tachycardia 138

Atrial Paroxysmal Tachycardia 138

Ventricular Paroxysmal Tachycardia 138

Ventricular Fibrillation 138

Phenomenon of Re-entry— Circus Movements as the Basis for Ventricular Fibrillation 139

Atrial Fibrillation 141

Atrial Flutter 142

Cardiac Arrest 142

UNIT Ⅳ The Circulation 144

CHAPTER 14 Overview of the Circulation; Medical Physics of Pressure, Flow, and Resistance 144

Physical Characteristics of the Circulation 144

Basic Theory of Circulatory Function 146

Interrelationships Among Pressure, Flow, and Resistance 146

Blood Flow 147

Blood Pressure 148

Resistance to Blood Flow 149

Effects of Pressure on Vascular Resistance and Tissue Blood Flow 151

CHAPTER 15 Vascular Distensibility, and Functions of the Arterial and Venous Systems 152

Vascular Distensibility 152

Vascular Compliance (or Capacitance) 152

Volume-Pressure Curves of the Arterial and Venous Circulations 152

Delayed Compliance (Stress-Relaxation) of Vessels 153

Arterial Pressure Pulsations 153

Transmission of Pressure Pulses to the Peripheral Arteries 154

Clinical Methods for Measuring Systolic and Diastolic Pressures 155

Veins and Their Functions 156

Venous Pressures—Right Atrial Pressure (Central Venous Pressure) and Peripheral Venous Pressures 156

Blood Reservoir Function of the Veins 160

Structure of the Microcirculation and Capillary System 162

CHAPTER 16 The Microcirculation and the Lymphatic System: Capillary Fluid Exchange, Interstitial Fluid, and Lymph Flow 162

Flow of Blood in the Capillaries—Vasomotion 163

Average Function of the Capillary System 163

Exchange of Nutrients and Other Substances Between the Blood and Interstitial Fluid 164

Diffusion Through the Capillary Membrane 164

The Interstitium and Interstitial Fluid 165

Proteins in the Plasma and Interstitial Fluid Are Especially Important in Controlling Plasma and Interstitial Fluid Volumes 166

Capillary Pressure 166

Interstitial Fluid Pressure 167

Plasma Colloid Osmotic Pressure 168

Exchange of Fluid Volume Through the Capillary Membrane 169

Interstitial Fluid Colloid Osmotic Pressure 169

Starling Equilibrium for Capillary Exchange 170

Lymphatic System 170

Lymph Channels of the Body 170

Formation of Lymph 171

Rate of Lymph Flow 172

Role of the Lymphatic System in Controlling Interstitial Fluid Protein Concentration, Interstitial Fluid Volume, and Interstitial Fluid Pressure 173

CHAPTER 17 Local Control of Blood Flow by the Tissues; and Humoral Regulation 175

Local Control of Blood Flow in Response to Tissue Needs 175

Mechanisms of Blood Flow Control 175

Acute Control of Local Blood Flow 176

Long-Term Blood Flow Regulation 179

Development of Collateral Circulation—A Phenomenon of Long-Term Local Blood Flow Regulation 180

Vasoconstrictor Agents 181

Vasodilator Agents 181

Humoral Regulation of the Circulation 181

Effects of Ions and Other Chemical Factors on Vascular Control 182

CHAPTER 18 Nervous Regulation of the Circulation, and Rapid Control of Arterial Pressure 184

Nervous Regulation of the Circulation 184

Autonomic Nervous System 184

Role of the Nervous System for Rapid Control of Arterial Pressure 187

Increase in Arterial Pressure During Muscle Exercise and Other Types of Stress 188

Reflex Mechanisms for Maintaining Normal Arterial Pressure 188

Central Nervous System Ischemic Response—Control of Arterial Pressure by the Brain s Vasomotor Center in Response to Diminished Brain Blood Flow 191

Role of the Skeletal Nerves and Skeletal Muscles in Increasing Cardiac Output and Arterial Pressure 192

Special Features of Nervous Control of Arterial Pressure 192

Respiratory Waves in the Arterial Pressure 193

Arterial Pressure Vasomotor Waves—Oscillation of the Pressure Reflex Control Systems 193

CHAPTER 19 Dominant Role of the Kidney in Long-Term Regulation of Arterial Pressure and in Hypertension: The Integrated System for Pressure Control 195

The Renal-Body Fluid System for Arterial Pressure Control 195

Quantitation of Pressure Diuresis as a Basis for Arterial Pressure Control 195

Hypertension (High Blood Pressure): This Is Often Caused by Excess Extracellular Fluid Volume 199

The Renin-Angiotensin System: Its Role in Pressure Control and in Hypertension 201

Components of the Renin-Angiotensin System 201

Types of Hypertension in Which Angiotensin Is Involved: Hypertension Caused by a Renin-Secreting Tumor or by Infusion of Angiotensin Ⅱ 203

Other Types of Hypertension Caused by Combinations of Volume-Loading and Vasoconstriction 205

“Essential Hypertension” in Human Beings 205

Summary of the Integrated, Multifaceted System for Arterial Pressure Regulation 207

CHAPTER 20 Cardiac Output, Venous Return, and Their Regulation 210

Normal Values for Cardiac Output at Rest and During Activity 210

Control of Cardiac Output by Venous Return—Role of the Frank-Starling Mechanism of the Heart 210

Cardiac Output Regulation Is the Sum of Blood Flow Regulation in All the Local Tissues of the Body—Tissue Metabolism Regulates Most Local Blood Flow 211

The Heart Has Limits for the Cardiac Output That It Can Achieve 212

What Is the Role of the Nervous System in Controlling Cardiac Output? 212

Pathologically High and Pathologically Low Cardiac Outputs 213

High Cardiac Output Is Almost Always Caused by Reduced Total Peripheral Resistance 213

Low Cardiac Output 214

A More Quantitative Analysis of Cardiac Output Regulation 214

Venous Return Curves 215

Cardiac Output Curves Used in Quantitative Analysis 215

Analysis of Cardiac Output and Right Atrial Pressure, Using Simultaneous Cardiac Output and Venous Return Curves 218

Methods for Measuring Cardiac Output 220

Pulsatile Output of the Heart as Measured by an Electromagnetic or Ultrasonic Flowmeter 220

Measurement of Cardiac Output by the Oxygen Fick Method 220

Indicator Dilution Method 221

CHAPTER 21 Muscle Blood Flow and Cardiac Output During Exercise; the Coronary Circulation and Ischemic Heart Disease 223

Blood Flow in Skeletal Muscle and Its Regulation During Exercise 223

Rate of Blood Flow Through the Muscles 223

Control of Blood Flow Through the Skeletal Muscles 223

Circulatory Readjustments During Exercise 224

Normal Coronary Blood Flow 226

Coronary Circulation 226

Physiologic Anatomy of the Coronary Blood Supply 226

Control of Coronary Blood Flow 227

Special Features of Cardiac Muscle Metabolism 228

Ischemie Heart Disease 229

Causes of Death After Acute Coronary Occlusion 230

Stages of Recovery from Acute Myocardial Infarction 231

Function of the Heart After Recovery from Myocardial Infarction 232

Pain in Coronary Disease 232

Surgical Treatment of Coronary Disease 233

Acute Effects of Moderate Cardiac Failure 235

Dynamics of the Circulation in Cardiac Failure 235

CHAPTER 22 Cardiac Failure 235

Chronic Stage of Failure-Fluid Retention Helps to Compensate Cardiac Output 236

Summary of the Changes That Occur After Acute Cardiac Failure— Compensated Heart Failure 237

Dynamics of Severe Cardiac Failure—Decompensated Heart Failure 237

Unilateral Left Heart Failure 239

Low-Output Cardiac Failure—Cardiogenic Shock 239

Edema in Patients with Cardiac Failure 239

Cardiac Reserve 241

Appendix 241

Quantitative Graphical Method for Analysis of Cardiac Failure 241

Normal Heart Sounds 245

Heart Sounds 245

CHAPTER 23 Heart Valves and Heart Sounds; Dynamics of Valvular and Congenital Heart Defects 245

Valvular Lesions 247

Abnormal Circulatory Dynamics in Valvular Heart Disease 248

Dynamics of the Circulation in Aortic Stenosis and Aortic Regurgitation 248

Dynamics of Mitral Stenosis and Mitral Regurgitation 248

Circulatory Dynamics During Exercise in Patients with Valvular Lesions 249

Abnormal Circulatory Dynamics in Congenital Heart Defects 249

Patent Ductus Arteriosus—A Left-to-Right Shunt 249

Tetralogy of Fallot—A Right-to-Left Shunt 251

Causes of Congenital Anomalies 251

Use of Extracorporeal Circulation During Cardiac Surgery 251

Hypertrophy of the Heart in Valvular and Congenital Heart Disease 252

CHAPTER 24 Circulatory Shock and Physiology of Its Treatment 253

Physiologic Causes of Shock 253

Circulatory Shock Caused by Decreased Cardiac Output 253

Circulatory Shock That Occurs Without Diminished Cardiac Output 253

What Happens to the Arterial Pressure in Circulatory Shock? 253

Tissue Deterioration Is the End Stage of Circulatory Shock, Whatever the Cause 253

Stages of Shock 254

Shock Caused by Hypovolemia—Hemorrhagic Shock 254

Relationship of Bleeding Volume to Cardiac Output and Arterial Pressure 254

Progressive and Nonprogressive Hemorrhagic Shock 255

Irreversible Shock 258

Anaphylactic Shock and Histamine Shock 259

Neurogenic Shock—Increased Vascular Capacity 259

Hypovolemic Shock Caused by Plasma Loss 259

Hypovolemic Shock Caused by Trauma 259

Septic Shock 260

Physiology of Treatment in Shock 260

Replacement Therapy 260

Treatment of Shock with Sympathomimetic Drugs—Sometimes Useful, Sometimes Not 261

Other Therapy 261

Circulatory Arrest 261

Effect of Circulatory Arrest on the Brain 261

Daily loss of Body Water 264

Daily Intake of Water 264

Fluid Intake and Output Are Balanced During Steady-State Conditions 264

CHAPTER 25 The Body Fluid Compartments: Extracellular and Intracellular Fluids; Interstitial Fluid and Edema 264

UNIT Ⅴ The Kidneys and Body Fluids 264

Body Fluid Compartments 265

Intracellular Fluid Compartment 265

Extracellular Fluid Compartment 266

Blood Volume 266

Constituents of Extracellular and Intracellular Fluids 266

Ionic Compositions of Plasma and Interstitial Fluid Are Similar 266

Important Constituents of the Intracellular Fluid 267

Determination of Volumes of Specitic Body Fluid Compartments 268

Measurement of Fluid Volumes in the Different Body Fluid Compartments; the Indicator-Dilution Principle 268

Basic Principles of Osmosis and Osmotic Pressure 269

Regulation of Fluid Exchange and Osmotic Equilibria Between Intracellular and Extracellular Fluid 269

Osmotic Equilibrium Is Maintained Between Intracellular and Extracellular Fluids 271

Volumes and Osmolalities of Extracellular and Intracellular Fluid in Abnormal States 272

Effect of Adding Saline Solution to the Extracellular Fluid 272

Glucose and Other Solutions Administered for Nutritive Purposes 273

Clinical Abnormalities of Fluid Volume Regulation: Hyponatremia and Hypernatremia 273

Edema: Excess Fluid in the Tissues 274

Intracellular Edema 274

Extracellular Edema 274

Causes of Hypernatremia: Water Loss or Excess Sodium 274

Causes of Hyponatremia: Excess Water or loss of Sodium 274

Safety Factors That Normally Prevent Edema 276

Fluids in the Potential Spaces of the Body 277

CHAPTER 26 Urine Formation by the Kidneys: I. Glomerular Filtration, Renal Blood Flow, and Their Control 279

Multiple Functions of the Kidneys in Homeostasis 279

Physiologic Anatomy of the Kidneys 280

General Organization of the Kidneys and Urinary Tract 280

Renal Blood Supply 281

The Nephron Is the Functional Unit of the Kidney 281

Urine Formation Results from Glomerular Filtration, Tubular Reabsorption, and Tubular Secretion 282

Filtration, Reabsorption, and Secretion of Different Substances 283

Glomerular Capillary Membrane 284

GFR Is About 20 Per Cent of the Renal Plasma Flow 284

Glomerular Filtration—The First Step In Urine Formation 284

Composition of the Glomerular Filtrate 284

Determinants of the Glomerular Filtration Rate 286

Increased Glomerular Capillary Filtration Coefficient (K1) Increases GFR 286

Increased Bowman s Capsule Hydrostatic Pressure Decreases GFR 287

Increased Glomerular Capillary Colloid Osmotic Pressure Decreases GFR 287

Increased Glomerular Capillary Hydrostatic Pressure Increases GFR 287

Renal Blood Flow 288

Determinants of Renal Blood Flow 288

Hormonal and Autacoid Control of Renal Circulation 289

Sympathetic Nervous System Activation Decreases GFR 289

Physiologic Control of Glomerular Filtration and Renal Blood Flow 289

Blood Flow in the Vasa Recta of the Renal Medulla Is Very Low Compared with Flow in the Renal Cortex 289

Autoregulation of GFR and Renal Blood Flow 290

Importance of GFR Autoregulation in Preventing Extreme Changes in Renal Excretion 291

Role of Tubuloglomerular Feedback in Autoregulation of GFR 291

Myogenic Autoregulation of Renal Blood Flow and GFR 293

Other Factors That Increase Renal Blood Flow and GFR: High Protein Intake and Increased Blood Glucose 293

CHAPTER 27 Urine Formation by the Kidneys: Ⅱ.Tubular Processing of the Glomerular Filtrate 295

Reabsorption and Secretion by the Renal Tubules 295

Tubular Reabsorption Is Selective and Quantitatively large 295

Tubular Reabsorption Includes Passive and Active Mechanisms 295

Active Transport 296

Passive Water Reabsorption by Osmosis Is Coupled Mainly to Sodium Reabsorption 299

Reabsorption of Chloride, Urea, and Other Solutes by Passive Diffusion 300

Reabsorption and Secretion Along Different Parts of the Nephron 300

Proximal Tubular Reabsorption 300

Solute and Water Transport in the Loop of Henle 302

Distal Tubule 303

late Distal Tubule and Cortical Collecting Tubule 303

Medullary Collecting Duct 304

Summary of Concentrations of Different Solutes in the Different Tubular Segments 304

Regulation of Tubular Reabsorption 305

Glomerulotubular Balance—The Ability of the Tubules to Increase Reabsorption Rate in Response to Increased Tubular load 305

Peritubular Capillary and Renal Interstitial Fluid Physical Forces 306

Effect of Arterial Pressure on Urine Output—The Pressure-Natriuresis and Pressure-Diuresis Mechanisms 308

Hormonal Control of Tubular Reabsorption 308

Use of Clearance Methods to Quantify Kidney Function 309

PAH Clearance Can Be Used to Estimate Renal Plasma Flow 311

Filtration Fraction Is Calculated from GFR Divided by Plasma Renal Flow 311

Calculation of Tubular Reabsorption or Secretion from Renal Clearances 311

CHAPTER 28 Regulation of Extracellular Fluid Osmolarity and Sodium Concentration 313

The Kidney Excretes Excess Water by Forming a Dilute Urine 313

Antidiuretic Hormone Controls Urine Concentration 313

Renal Mechanisms for Excreting a Dilute Urine 313

The Countercurrent Mechanism Produces a Hyperosmotic Renal Medullary Interstitium 315

Requirements for Excreting a Concentrated Urine—High ADH Levels and Hyperosmotic Renal Medulla 315

Obligatory Urine Volume 315

The Kidney Conserves Water by Excreting a Concentrated Urine 315

Role of the Distal Tubule and Collecting Ducts in Excreting a Concentrated Urine 317

Urea Contributes to Hyperosmotic Renal Medullary Interstitium and to a Concentrated Urine 318

Countercurrent Exchange in the Vasa Recta Preserves Hyperosmolarity of the Renal Medulla 319

Summary of Urine Concentrating Mechanism and Changes in Osmolarity in Different Segments of the Tubules 320

Quantifying Renal Urine Concentration and Dilution: Free Water and Osmolar Clearances 321

Disorders of Urinary Concentrating Ability 322

Control of Extracellular Fluid Osmolarity and Sodium Concentration 322

Estimating Plasma Osmolarity from Plasma Sodium Concentration 322

ADH Synthesis in Supraoptic and Paraventricular Nuclei of the Hypothalamus and ADH Release from the Posterior Pituitary 323

Osmoreceptor-ADH Feedback System 323

Cardiovascular Reflex Stimulation of ADH Release by Decreased Arterial Pressure and/or Decreased Blood Volume 324

Quantitative Importance of Cardiovascular Reflexes and Osmolarity in Stimulating ADH Secretion 324

Other Stimuli for ADH Secretion 324

Role of Thirst in Controlling Extracellular Fluid Osmolarity and Sodium Concentration 325

Central Nervous System Centers for Thirst 325

Stimuli for Thirst 325

Threshold for Osmolar Stimulus of Drinking 326

Integrated Responses of Osmoreceptor-ADH and Thirst Mechanisms in Controlling Extracellular Fluid Osmolarity and Sodium Concentration 326

Role of Angiotensin Ⅱ and Aldosterone in Controlling Extracellular Fluid Osmolarity and Sodium Concentration 327

Salt-Appetite Mechanism for Controlling Extracellular Fluid Sodium Concentration and Volume 327

Sodium Excretion Is Controlled by Altering Glomerular Filtration or Tubular Sodium Reabsorption Rates 329

Sodium Excretion Is Precisely Matched to Intake Under Steady-State Conditions 329

CHAPTER 29 Integration of Renal Mechanisms for Control of Blood Volume and Extracellular Fluid Volume; and Renal Regulation of Potassium, Calcium, Phosphate, and Magnesium 329

Control Mechanisms for Regulating Sodium and Water Excretion 329

Importance of Pressure Natriuresis and Pressure Diuresis in Maintaining Body Sodium and Fluid Balance 330

Pressure Natriuresis and Diuresis Are Key Components of a Renal-Body Fluid Feedback for Regulating Body Fluid Volumes and Arterial Pressure 330

Precision of Blood Volume and Extracellular Fluid Volume Regulation 331

Distribution of Extracellular Fluid Between the Interstitial Spaces and Vascular System 332

Nervous and Hormonal Factors Increase the Effectiveness of Renal-Body Fluid Feedback Control 332

Sympathetic Nervous System Control of Renal Excretion: The Arterial Baroreceptor and Low-Pressure Stretch Receptor Reflexes 332

Role of Angiotensin Ⅱ in Controlling Renal Excretion 333

Role of Aldosterone in Controlling Renal Excretion 334

Role of ADH in Controlling Renal Water Excretion 334

Conditions That Cause Large Increases in Blood Volume and Extracellular Fluid Volume 335

Increased Blood Volume and Extracellular Fluid Volume Caused by Heart Diseases 335

Role of Atrial Natriuretic Peptide in Controlling Renal Excretion 335

Integrated Responses to Changes in Sodium Intake 335

Increased Blood Volume Caused by Increased Capacity of the Circulation 336

Conditions That Cause Large Increases in Extracellular Fluid Volume but with Normal Blood Volume 336

Nephrotic Syndrome—Loss of Plasma Proteins in the Urine and Sodium Retention by the Kidneys 336

Liver Cirrhosis—Decreased Synthesis of Plasma Proteins by the Liver and Sodium Retention by the Kidneys 336

Regulation of Potassium Excretion and Potassium Concentration in the Extracellular Fluid 336

Regulation of Internal Potassium Distribution 337

Overview of Renal Potassium Excretion 338

Summary of Factors That Regulate Potassium Secretion: Plasma Potassium Concentration, Aldosterone, Tubular Flow Rate, and Hydrogen Ion 339

Potassium Secretion in the Principal Cells of the Late Distal and Cortical Collecting Tubules 339

Control of Renal Calcium Excretion and Extracellular Calcium Ion Concentration 342

Control of Calcium Excretion by the Kidneys 343

Regulation of Renal Phosphate Excretion 343

Control of Renal Magnesium Excretion and Extracellular Magnesium Ion Concentration 344

CHAPTER 30 Regulation of Acid-Base Balance 346

Hydrogen Ion Concentration Is Precisely Regulated 346

Acids and Bases—Their Definitions and Meanings 346

Defenses Against Changes in Hydrogen Ion Concentration: Buffers, Lungs, and Kidneys 347

Buffering of Hydrogen Ions in the Body Fluids 347

Quantitative Dynamics of the Bicarbonate Buffer System 348

The Bicarbonate Buffer System 348

The Phosphate Buffer System 350

Proteins: Important Intracellular Buffers 350

Isohydric Principle: All Buffers in a Common Solution Are in Equilibrium with the Same Hydrogen Ion Concentration 350

Respiratory Regulation of Acid-Base Balance 351

Pulmonary Expiration of CO2 Balances Metabolic Formation of CO2 351

Increasing Alveolar Ventilation Decreases Extracellular Fluid Hydrogen Ion Concentration and Raises pH 351

Increased Hydrogen Ion Concentration Stimulates Alveolar Ventilation 351

Renal Control of Acid-Base Balance 352

Secretion of Hydrogen Ions and Reabsorption of Bicarbonate Ions by the Renal Tubule 353

Hydrogen Ions Are Secreted by Secondary Active Transport in the Early Tubular Segments 353

Filtered Bicarbonate Ions Are Reabsorbed by Interaction with Hydrogen Ions in the Tubules 354

Combination of Excess Hydrogen Ions With Phosphate and Ammonia Buffers in the Tubule—A Mechanism for Generating New Bicarbonate Ions 355

Primary Active Secretion of Hydrogen Ions in the Intercalated Cells of Late Distal and Collecting Tubules 355

The Phosphate Buffer System Carries Excess Hydrogen Ions into the Urine and Generates New Bicarbonate 356

Excretion of Excess Hydrogen Ions and Generation of New Bicarbonate by the Ammonia Buffer System 356

Quantifying Renal Acid-Base Excretion 357

Regulation of Renal Tubular Hydrogen Ion Secretion 357

Renal Correction of Acidosis—Increased Excretion of Hydrogen Ions and Addition of Bicarbonate Ions to the Extracellular Fluid 358

Acidosis Decreases the Ratio of HCO3-/H+ in Renal Tubular Fluid 358

Respiratory Alkalosis Results from Increased Ventilation and Decreased PCO2 359

Respiratory Acidosis Is Caused by Decreased Ventilation and Increased PCO2 359

Clinical Causes of Acid-Base Disorders 359

Alkalosis Increases the Ratio of HCO3-/H+ in Renal Tubular Fluid 359

Renal Correction of Alkalosis—Decreased Tubular Secretion of Hydrogen Ions and Increased Excretion of Bicarbonate Ions 359

Metabolic Acidosis Results from Decreased Extracellular Fluid Bicarbonate Concentration 360

Metabolic Alkalosis Is Caused by Increased Extracellular Fluid Bicarbonate Concentration 360

Treatment of Acidosis or Alkalosis 360

Clinical Measurements and Analysis of Acid-Base Disorders 361

Complex Acid-Base Disorders and the Use of the Acid-Base Nomogram for Diagnosis 361

Use of Anion Gap to Diagnose Acid-Base Disorders 362

Innervation of the Bladder 364

Physiologic Anatomy and Nervous Connections of the Bladder 364

Transport of Urine from the Kidney Through the Ureters and Into the Bladder 364

CHAPTER 31 Micturition, Diuretics, and Kidney Diseases 364

Micturition 364

Filling of the Bladder and Bladder Wall Tone; The Cystometrogram 365

Micturition Reflex 366

Facilitation or Inhibition of Micturition by the Brain 366

Abnormalities of Micturition 366

Diuretics and Their Mechanisms of Action 367

Osmotic Diuretics Decrease Water Reabsorption by Increasing Osmotic Pressure of Tubular Fluid 367

Carbonic Anhydrase Inhibitors Block Sodium-Bicarbonate Reabsorption in the Proximal Tubules 368

Diuretics That Block Sodium Channels in the Collecting Tubules Decrease Sodium Reabsorption 368

Competitive Inhibitors of Aldosterone Decrease Sodium Reabsorption from and Potassium Secretion into the Cortical Collecting Tubule 368

Thiazide Diuretics Inhibit Sodium-Chloride Reabsorption in the Early Distal Tubule 368

Loop Diuretics Decrease Active Sodium-Chloride-Potassium Reabsorption in the Thick Ascending Loop of Henle 368

Kidney Diseases 369

Acute Renal Failure 369

Prerenal Acute Renal Failure Caused by Decreased Blood Flow to the Kidney 369

Intrarenal Acute Renal Failure Caused by Abnormalities Within the Kidney 369

Postrenal Acute Renal Failure Caused by Abnormalities of the Lower Urinary Tract 370

Physiologic Effects of Acute Renal Failure 370

Chronic Renal Failure: An Irreversible Decrease in the Number of Functional Nephrons 371

Vicious Circle of Chronic Renal Failure Leading to End-Stage Renal Disease 371

Injury to the Renal Vasculature as a Cause of Chronic Renal Failure 371

Injury to the Glomeruli as a Cause of Chronic Renal Failure—Glomerulonephritis 372

Nephrotic Syndrome—Excretion of Protein in the Urine Because of Increased Glomerular Permeability 373

Abnormal Nephron Function in Chronic Renal Failure 373

Injury to the Renal Interstitium as a Cause of Chronic Renal Failure—Pyelonephritis 373

Effects of Renal Failure on the Body Fluids—Uremia 375

Hypertension and Kidney Disease 376

Specific Tubular Disorders 377

Treatment of Renal Failure by Dialysis With an Artificial Kidney 377

UNIT Ⅵ Blood Cells, Immunity, and Blood Clotting 382

CHAPTER 32 Red Blood Cells, Anemia, and Polycythemia 382

Red Blood Cells (Erythrocytes) 382

Production of Red Blood Cells 382

Formation of Hemoglobin 386

Iron Metabolism 387

Destruction of Red Blood Cells 389

The Anemias 389

Effects of Anemia on the Circulatory System 390

Polycythemia 390

Effect of Polycythemia on the Circulatory System 390

CHAPTER 33 Resistance of the Body to Infection: Ⅰ. Leukocytes, Granulocytes, the Monocyte-Macrophage System, and Inflammation 392

Leukocytes (White Blood Cells) 392

General Characteristics of Leukocytes 392

Genesis of the White Blood Cells 392

Life Span of the White Blood Cells 393

Defense Properties of Neutrophils and Macrophages 393

Phagocytosis 394

Monocyte-Macrophage System (Reticuloendothelial System) 395

Inflammation and Role of Neutrophils and Macrophages 397

Inflammation 397

Macrophage and Neutrophil Responses During Inflammation 397

Eosinophils 399

Basophils 399

Leukopenia 399

The Leukemias 400

Effects of Leukemia on the Body 400

Both Types of Acquired Immunity Are Initiated by Antigens 402

Basic Types of Acquired Immunity 402

Acquired Immunity 402

Innate Immunity 402

CHAPTER 34 Resistance of the Body to Infection: Ⅱ. Immunity and Allergy 402

Lymphocytes Are the Basis of Acquired Immunity 403

Preprocessing of the T and B Lymphocytes 403

T Lymphocytes and B-Lymphocyte Antibodies React Highly Specifically Against Specific Antigens—Role of Lymphocyte Clones 404

Origin of the Many Clones of Lymphocytes 405

Specific Attributes of the B-Lymphocyte System—Humoral Immunity and the Antibodies 405

Special Attributes of the T-Lymphocyte System—Activated T Cells and Cell-Mediated Immunity 408

Several Types of T Cells and Their Different Functions 409

Tolerance of the Acquired Immunity System to One s Own Tissues—Role of Preprocessing in the Thymus and Bone Marrow 410

Allergies in the So-Called Allergic Person, Who Has Excess IgE Antibodies 411

Allergy Caused by Activated T Cells: Delayed-Reaction Allergy 411

Immunization 411

Passive Immunity 411

Allergy and Hypersensitivity 411

CHAPTER 35 Blood Groups; Transfusion; Tissue and Organ Transplantation 413

Antigenicity Causes Immune Reactions of Blood 413

O-A-B Blood Groups 413

A and B Antigens—Agglutinogens 413

Agglutinins 413

Agglutination Process in Transfusion Reactions 414

Blood Typing 414

Rh Immune Response 415

Rh Blood Types 415

Transfusion Reactions Resulting from Mismatched Blood Types 416

Transplantation of Tissues and Organs 416

Attempts to Overcome the Immune Reaction to Transplanted Tissue 417

CHAPTER 36 Hemostasis and Blood Coagulation 419

Events in Hemostasis 419

Vascular Constriction 419

Formation of the Platelet Plug 419

Blood Coagulation in the Ruptured Vessel 420

Conversion of Fibrinogen to Fibrin—Formation of the Clot 421

Conversion of Prothrombin to Thrombin 421

Fibrous Organization or Dissolution of the Blood Clot 421

Mechanism of Blood Coagulation 421

Vicious Circle of Clot Formation 422

Initiation of Coagulation: Formation of Prothrombin Activator 422

Prevention of Blood Clotting in the Normal Vascular System—The Intravascular Anticoagulants 425

Lysis of Blood Clots—Plasmin 425

Conditions That Cause Excessive Bleeding in Human Beings 426

Decreased Prothrombin, Factor Ⅶ, Factor Ⅸ, and Factor Ⅹ Caused by Vitamin K Deficiency 426

Hemophilia 426

Thrombocytopenia 426

Disseminated Intravascular Coagulation 427

Thromboembolic Conditions in the Human Being 427

Femoral Venous Thrombosis and Massive Pulmonary Embolism 427

Anticoagulants for Clinical Use 428

Heparin as an Intravenous Anticoagulant 428

Coumarins as Anticoagulants 428

Prevention of Blood Coagulation Outside the Body 428

Blood Coagulation Tests 428

Bleeding Time 428

Clotting Time 428

Prothrombin Time 429

Muscles That Cause Lung Expansion and Contraction 432

Mechanics of Pulmonary Ventilation 432

Movement of Air In and Out of the Lungs—and the Pressures That Cause the Movement 432

CHAPTER 37 Pulmonary Ventilation 432

UNIT Ⅶ Respiration 432

Effect of the Thoracic Cage on Lung Expansibility 435

Work of Breathing 435

Pulmonary Volumes and Capacities 436

Recording Changes in Pulmonary Volume—Spirometry 436

Abbreviations and Symbols Used in Pulmonary Function Studies 437

Determination of Functional Residual Capacity, Residual Volume, and Total Lung Capacity—Helium Dilution Method 437

Minute Respiratory Volume Equals Respiratory Rate Times Tidal Volume 438

Alveolar Ventilation 438

Rate of Alveolar Ventilation 439

Dead Space and Its Effect on Alveolar Ventilation 439

Functions of the Respiratory Passageways 440

Trachea, Bronchi, and Bronchioles 440

Normal Respiratory Functions of the Nose 441

Vocalization 442

CHAPTER 38 Pulmonary Circulation; Pulmonary Edema; Pleural Fluid 444

Physiologic Anatomy of the Pulmonary Circulatory System 444

Pressures in the Pulmonary System 444

Blood Volume of the Lungs 445

Blood Flow Through the Lungs and Its Distribution 445

Effect of Hydrostatic Pressure Gradients in the Lungs on Regional Pulmonary Blood Flow 446

Zones 1, 2, and 3 of Pulmonary Blood Flow 446

Function of the Pulmonary Circulation When the Left Atrial Pressure Rises as a Result of Left-Sided Heart Failure 447

Effect of Increased Cardiac Output on the Pulmonary Circulation During Heavy Exercise 447

Capillary Exchange of Fluid in the Lungs, and Pulmonary Interstitial Fluid Dynamics 448

Pulmonary Capillary Dynamics 448

Pulmonary Edema 449

Fluids in the Pleural Cavity 450

CHAPTER 39 Physical Principles of Gas Exchange; Diffusion of Oxygen and Carbon Dioxide Through the Respiratory Membrane 452

Physics of Gas Diffusion and Gas Partial Pressures 452

Molecular Basis of Gas Diffusion 452

Gas Pressures in a Mixture of Gases— Partial Pressures of Individual Gases 452

Pressures of Gases Dissolved in Water and Tissues 452

Vapor Pressure of Water 453

Diffusion of Gases Through Fluids—Pressure Difference Causes Net Diffusion 453

Rate at Which Alveolar Air Is Renewed by Atmospheric Air 454

Diffusion of Gases Through Tissues 454

Composition of Alveolar Air—Its Relation to Atmospheric Air 454

Oxygen Concentration and Partial Pressure in the Alveoli 455

CO2 Concentration and Partial Pressure in the Alveoli 455

Expired Air 456

Diffusion of Gases Through the Respiratory Membrane 456

Factors That Affect the Rate of Gas Diffusion Through the Respiratory Membrane 457

Diffusing Capacity of the Respiratory Membrane 458

Effect of the Ventilation-Perfusion Ratio on Alveolar Gas Concentration 460

PO2-PCO2, VA/Q Diagram 460

Abnormalities of Ventilation-Perfusion Ratio 461

Concept of Physiologic Dead Space (When VA/Q Is Creater Than Normal) 461

Concept of Physiologic Shunt (When VA/Q Is Below Normal) 461

CHAPTER 40 Transport of Oxygen and Carbon Dioxide in the Blood and Body Fluids 463

Pressures of Oxygen and Carbon Dioxide in the Lungs, Blood, and Tissues 463

Uptake of Oxygen by the Pulmonary Blood 463

Transport of Oxygen in the Arterial Blood 464

Diffusion of Oxygen from the Peripheral Capillaries into the Tissue Fluid 464

Diffusion of Oxygen from the Peripheral Tissue Capillaries to the Tissue Cells 465

Diffusion of Carbon Dioxide from the Peripheral Tissue Cells into the Tissue Capillaries and from the Pulmonary Capillaries into the Alveoli 465

Transport of Oxygen in the Blood 466

Reversible Combination of Oxygen with Hemoglobin 466

Effect of Hemoglobin to Buffer the Tissue Po2 467

Factors That Shift the Oxygen-Hemoglobin Dissociation Curve—Their Importance for Oxygen Transport 468

Metabolic Use of Oxygen by the Cells 469

Transport of Oxygen in the Dissolved State 469

Combination of Hemoglobin with Carbon Monoxide—Displacement of Oxygen 469

Transport of Carbon Dioxide in the Blood 470

Chemical Forms in Which Carbon Dioxide Is Transported 470

Transport of Carbon Dioxide in the Form of Bicarbonate Ion 470

Carbon Dioxide Dissociation Curve 471

When Oxygen Binds with Hemoglobin, Carbon Dioxide Is Released—The Haldane Effect—to Increase CO2 Transport 471

Change in Blood Acidity During Carbon Dioxide Transport 472

Respiratory Exchange Ratio 472

Dorsal Respiratory Group of Neurons—Its Control of Inspiration and of Respiratory Rhythm 474

Respiratory Center 474

CHAPTER 41 Regulation of Respiration 474

The Pneumotaxic Center Limits the Duration of Inspiration and Increases the Respiratory Rate 475

Ventral Respiratory Group of Neurons Functions in Both Inspiration and Expiration 475

Possibility of an Apneustic Center in the Lower Pons 475

Lung Inflation Signals Limit Inspiration—The Hering-Breuer Inflation Reflex 475

Control of Overall Respiratory Center Activity 476

Chemical Control of Respiration 476

Direct Chemical Control of Respiratory Center Activity by Carbon Dioxide and Hydrogen Ions 476

Peripheral Chemoreceptor System for Control of Respiratory Activity—Role of Oxygen in Respiratory Control 477

Composite Effects of Pco2, pH, and Po2 on Alveolar Ventilation 479

Regulation of Respiration During Exercise 479

Other Factors That Affect Respiration 481

Periodic Breathing 482

CHAPTER 42 Respiratory Insufficiency—Pathophysiology, Diagnosis, Oxygen Therapy 484

Useful Methods for Studying Respiratory Abnormalities 484

Study of Blood Gases and Blood pH 484

Measurement of Maximum Expiratory Flow 485

Forced Expiratory Vital Capacity and Forced Expiratory Volume 486

Physiologic Peculiarities of Specific Pulmonary Abnormalities 486

Chronic Pulmonary Emphysema 486

Pneumonia 488

Atelectasis 488

Asthma 489

Tuberculosis 489

Oxygen Therapy in Different Types of Hypoxia 490

Hypoxia and Oxygen Therapy 490

Hypercapnia 491

Cyanosis 491

Dyspnea 491

Artificial Respiration 492

UNIT Ⅷ Aviation, Space, and Deep-Sea Diving Physiology 496

CHAPTER 43 Aviation, High-Altitude, and Space Physiology 496

Effects of Low Oxygen Pressure on the Body 496

Alveolar PO2 at Different Elevations 496

Effect of Breathing Pure Oxygen on Alveolar PO2 at Different Altitudes 496

Acclimatization to Low PO2 497

Acute Effects of Hypoxia 497

Natural Acclimatization of Native Human Beings Living at High Altitudes 498

Work Capacity at High Altitudes—The Effect of Acclimatization 499

Chronic Mountain Sickness 499

Acute Mountain Sickness and High-Altitude Pulmonary Edema 499

Effects of Acceleratory Forces on the Body in Aviation and Space Physiology 500

Centrifugal Acceleratory Forces 500

Effects of Linear Acceleratory Forces on the Body 501

Artificial Climate in the Sealed Spacecraft 502

Weightlessness in Space 502

Effect of High Partial Pressures of Gases on the Body 504

Oxygen Toxicity at High Pressures 504

CHAPTER 44 Physiology of Deep-Sea Diving and Other Hyperbaric Conditions 504

Decompression of the Diver After Exposure to High Pressures 506

Scuba (Self-Contained Underwater Breathing Apparatus)Diving 508

Special Physiologic Problems in Submarines 508

Hyperbaric Oxygen Therapy 509

UNIT Ⅸ The Nervous System: A. General Principles and Sensory Physiology 512

CHAPTER 45 Organization of the Nervous System; Basic Functions of Synapses and Transmitter Substances 512

General Design of the Nervous System 512

The Central Nervous System Neuron—The Basic Functional Unit 512

Sensory Division of the Nervous System—Sensory Receptors 512

Motor Division—The Effectors 512

Processing of Information— Integrative Function of the Nervous System 513

Storage of Information—Memory 514

Major Levels of Central Nervous System Function 514

Spinal Cord Level 514

Lower Brain or Subcortical Level 514

Higher Brain or Cortical Level 515

Comparison of the Nervous System With an Electronic Computer 515

Central Nervous System Synapses 515

Types of Synapses—Chemical and Electrical 515

Physiologic Anatomy of the Synapse 516

Chemical Substances That Function as Synaptic Transmitters 519

Electrical Events During Neuronal Excitation 521

Electrical Events in Neuronal Inhibition 522

Special Functions of Dendrites in Exciting Neurons 524

Relation of State of Excitation of the Neuron to Rate of Firing 525

Some Special Characteristics of Synaptic Transmission 525

CHAPTER 46 Sensory Receptors; Neuronal Circuits for Processing Information 528

Types of Sensory Receptors and the Sensory Stimuli They Detect 528

Differential Sensitivity of Receptors 528

Transduction of Sensory Stimuli Into Nerve Impulses 529

Local Electrical Currents at Nerve Endings—Receptor Potentials 529

Adaptation of Receptors 531

Nerve Fibers That Transmit Different Types of Signals and Their Physiologic Classification 532

Transmission and Processing of Signals in Neuronal Pools 533

Transmission of Signals of Different Intensity in Nerve Tracts—Spatial and Temporal Summation 533

Relaying of Signals Through Neuronal Pools 534

Prolongation of a Signal by a Neuronal Pool— Afterdischarge 536

Instability and Stability of Neuronal Circuits 538

Inhibitory Circuits as a Mechanism for Stabilizing Nervous System Function 538

Synaptic Fatigue as a Means of Stabilizing the Nervous System 538

CHAPTER 47 Somatic Sensations: Ⅰ. General Organization; the Tactile and Position Senses 540

Classification of Somatic Senses 540

Detection and Transmission of Tactile Sensations 540

Detection of Vibration 541

Anatomy of the Dorsal Column-Medial Lemniscal System 542

Transmission in the Dorsal Column-Medial Lemniscal System 542

Anterolateral System 542

Sensory Pathways for Transmitting Somatic Signals into the Central Nervous System 542

Tickling and Itch 542

Dorsal Column-Medial Lemniscal System 542

Somatosensory Cortex 544

Somatosensory Association Areas 546

Overall Characteristics of Signal Transmission and Analysis in the Dorsal Column-Medial Lemniscal System 546

Interpretation of Sensory Stimulus Intensity 548

Judgment of Stimulus Intensity 548

Position Senses 548

Transmission of Less Critical Sensory Signals in the Anterolateral Pathway 549

Anatomy of the Anterolateral Pathway 549

Cortical Control of Sensory Sensitivity— Corticofugal Signals 550

Some Special Aspects of Somatosensory Function 550

Function of the Thalamus in Somatic Sensation 550

Segmental Fields of Sensation—The Dermatomes 551

CHAPTER 48 Somatic Sensations: Ⅱ. Pain, Headache, and Thermal Sensations 552

Types of Pain and Their Qualities—Fast Pain and Slow Pain 552

Pain Receptors and Their Stimulation 552

Rate of Tissue Damage as a Stimulus for Pain 553

Dual Transmission of Pain Signals into the Central Nervous System 553

Dual Pain Pathways in the Cord and Brain Stem—The Neospinothalamic Tract and the Paleospinothalamic Tract 554

Pain Suppression ( Analgesia ) System in the Brain and Spinal Cord 555

The Brain s Opiate System—The Endorphins and Enkephalins 556

Causes of True Visceral Pain 557

Visceral Pain 557

Inhibition of Pain Transmission by Tactile Sensory Signals 557

Referred Pain 557

Treatment of Pain by Electrical Stimulation 557

Parietal Pain Caused by Visceral Damage 558

Localization of Visceral Pain—The Visceral and the Parietal Pain Transmission Pathways 558

Some Clinical Abnormalities of Pain and Other Somatic Sensations 559

Hyperalgesia 559

Thalamic Syndrome 559

Herpes Zoster (Shingles) 559

Tic Douloureux 559

Headache of Intracranial Origin 560

Headache 560

Brown-Sequard Syndrome 560

Extracranial Types of Headache 561

Thermal Sensations 561

Thermal Receptors and Their Excitation 561

Transmission of Thermal Signals in the Nervous System 562

UNIT Ⅹ The Nervous System: B. The Special Senses 566

CHAPTER 49 The Eye: Ⅰ. Optics of Vision 566

Physical Principles of Optics 566

Refraction of Light 566

Application of Refractive Principles to Lenses 566

Focal Length of a Lens 567

Formation of an Image by a Convex Lens 568

Measurement of the Refractive Power of a Lens—The Diopter 569

Optics of the Eye 569

The Eye as a Camera 569

Mechanism of Accommodation 570

Pupillary Diameter 571

Errors of Refraction 571

Visual Acuity 573

Determination of Distance of an Object from the Eye—Depth Perception 574

Ophthalmoscope 574

Formation of Aqueous Humor by the Ciliary Body 575

Fluid System of the Eye—Intraocular Fluid 575

Outflow of Aqueous Humor from the Eye 576

Intraocular Pressure 576

CHAPTER 50 The Eye: Ⅱ. Receptor and Neural Function of the Retina 578

Anatomy and Function of the Structural Elements of the Retina 578

Photochemistry of Vision 579

Rhodopsin-Retinal Visual Cycle, and Excitation of the Rods 580

Automatic Regulation of Retinal Sensitivity—Light and Dark Adaptation 582

Color Vision 584

Tricolor Mechanism of Color Detection 584

Color Blindness 584

Neural Circuitry of the Retina 586

Neural Function of the Retina 586

Ganglion Cells 588

Excitation of the Ganglion Cells 588

CHAPTER 51 The Eye: Ⅲ. Central Neurophysiology of Vision 591

Visual Pathways 591

Function of the Dorsal Lateral Geniculate Nucleus 591

Organization and Function of the Visual Cortex 592

Layered Structure of the Primary Visual Cortex 593

Two Major Pathways for Analysis of Visual Information—(1) The Fast Position and Motion Pathway; (2) The Accurate Color Pathway 594

Neuronal Patterns of Stimulation During Analysis of the Visual Image 594

Fields of Vision; Perimetry 595

Effect of Removing the Primary Visual Cortex 595

Detection of Color 595

Eye Movements and Their Control 596

Fixation Movements of the Eyes 596

Fusion of the Visual Images from the Two Eyes 598

Autonomic Control of Accommodation and Pupillary Aperture 599

Control of Accommodation (Focusing the Eyes) 599

Control of Pupillary Diameter 600

CHAPTER 52 The Sense of Hearing 602

Tympanic Membrane and the Ossicular System 602

Conduction of Sound from the Tympanic Membrane to the Cochlea 602

Functional Anatomy of the Cochlea 603

The Cochlea 603

Transmission of Sound Through Bone 603

Transmission of Sound Waves in the Cochlea—The Traveling Wave 604

Function of the Organ of Corti 605

Determination of Sound Frequency—The Place Principle 607

Determination of Loudness 607

Central Auditory Mechanisms 608

Auditory Pathways 608

Function of the Cerebral Cortex in Hearing 609

Determination of the Direction from Which Sound Comes 610

Hearing Abnormalities 611

Types of Deafness 611

Centrifugal Signals from the Central Nervous System to Lower Auditory Centers 611

CHAPTER 53 The Chemical Senses—Taste and Smell 613

Sense of Taste 613

Primary Sensations of Taste 613

Taste Bud and Its Function 614

Transmission of Taste Signals into the Central Nervous System 615

Taste Preference and Control of the Diet 616

Sense of Smell 616

Olfactory Membrane 616

Stimulation of the Olfactory Cells 617

Transmission of Smell Signals into the Central Nervous System 618

Organization of the Spinal Cord for Motor Functions 622

CHAPTER 54 Motor Functions of the Spinal Cord; The Cord Reflexes 622

UNIT Ⅺ The Nervous System: C. Motor and Integrative Neurophysiology 622

Muscle Sensory Receptors—Muscle Spindles and Golgi Tendon Organs—and Their Roles in Muscle Control 624

Receptor Function of the Muscle Spindle 624

Muscle Stretch Reflex 625

Role of the Muscle Spindle in Voluntary Motor Activity 626

Clinical Applications of the Stretch Reflex 627

Golgi Tendon Reflex 628

Function of the Muscle Spindles and Golgi Tendon Organs in Conjunction with Motor Control from Higher Levels of the Brain 628

Flexor Reflex and the Withdrawal Reflexes 629

Reflexes of Posture and Locomotion 630

Postural and Locomotive Reflexes of the Cord 630

Reciprocal Inhibition and Reciprocal Innervation 630

Crossed Extensor Reflex 630

Scratch Reflex 631

Spinal Cord Reflexes That Cause Muscle Spasm 632

Autonomic Reflexes in the Spinal Cord 632

Spinal Cord Transection and Spinal Shock 632

CHAPTER 55 Cortical and Brain Stem Control of Motor Function 634

The Motor Cortex and Corticospinal Tract 634

Primary Motor Cortex 634

Premotor Area 634

Some Specialized Areas of Motor Control Found in the Human Motor Cortex 635

Supplementary Motor Area 635

Transmission of Signals from the Motor Cortex to the Muscles 636

Incoming Fiber Pathways to the Motor Cortex 637

The Red Nucleus Serves as an Alternative Pathway for Transmitting Cortical Signals to the Spinal Cord 637

Extrapyramidal System 638

Excitation of the Spinal Cord Motor Control Areas by the Primary Motor Cortex and the Red Nucleus 638

Role of the Brain Stem in Controlling Motor Function 640

Support of the Body Against Gravity—Roles of the Reticular and Vestibular Nuclei 640

Vestibular Sensations and the Maintenance of Equilibrium 641

Vestibular Apparatus 641

Function of the Utricle and Saccule in the Maintenance of Static Equilibrium 643

Detection of Head Rotation by the Semicircular Ducts 644

Vestibular Mechanisms for Stabilizing the Eyes 645

Other Factors Concerned with Equilibrium 645

Functions of Brain Stem Nuclei in Controlling Subconscious, Stereotyped Movements 646

CHAPTER 56 The Cerebellum, the Basal Ganglia, and Overall Motor Control 647

The Cerebellum and Its Motor Functions 647

Anatomical Functional Areas of the Cerebellum 647

Neuronal Circuit of the Cerebellum 648

Function of the Cerebellum in Overall Motor Control 652

Clinical Abnormalities of the Cerebellum 655

The Basal Ganglia—Their Motor Functions 656

Function of the Basal Ganglia in Executing Patterns of Motor Activity—The Putamen Circuit 657

Role of the Basal Ganglia for Cognitive Control of Sequences of Motor Patterns—The Caudate Circuit 657

Function of the Basal Ganglia to Change the Timing and to Scale the Intensity of Movements 658

Functions of Specific Neurotransmitter Substances in the Basal Ganglial System 659

Clinical Syndromes Resulting from Damage to the Basal Ganglia 659

Integration of the Many Parts of the Total Motor Control System 660

Spinal Level 660

Hindbrain Level 660

Motor Cortex Level 660

What Drives Us to Action? 661

CHAPTER 57 The Cerebral Cortex; Intellectual Functions of the Brain; and Learning and Memory 663

Physiologic Anatomy of the Cerebral Cortex 663

Functions of Specific Cortical Areas 663

Association Areas 665

Comprehensive Interpretative Function Of the Posterior Superior Temporal Lobe— Wernicke s Area (a General Interpretative Area) 666

Functions of the Parieto-occipitotemporal Cortex in the Nondominant Hemisphere 668

Higher Intellectual Functions of the Prefrontal Association Area 668

Function of the Brain in Communication—Language Input and Language Output 669

Function of the Corpus Callosum and Anterior Commissure to Transfer Thoughts, Memories. Training, and Other Information Between the Two Cerebral Hemispheres 671

Thoughts, Consciousness, and Memory 671

Memory—Roles of Synaptic Facilitation and Synaptic Inhibition 672

Short-Term Memory 673

Intermediate Long-Term Memory 673

Long-Term Memory 674

Consolidation of Memory 675

Control of Cerebral Activity by Continuous Excitatory Signals from the Brain Stem 678

Activating-Driving Systems of the Brain 678

CHAPTER 58 Behavioral and Motivational Mechanisms of the Brain—The Limbic System and the Hypothalamus 678

Neurohormonal Control of Brain Activity 679

The Limbic System 681

Functional Anatomy of the Limbic System: the Key Position of the Hypothalamus 681

The Hypothalamus, a Major Control Headquarters for the Limbic System 682

Vegetative and Endocrine Control Functions of the Hypothalamus 682

Behavioral Functions of the Hypothalamus and Associated Limbic Structures 684

Reward and Punishment Function of the Limbic System 684

Importance of Reward and