Board Review Series • Reflects USMLE changes • Approximately 350 USMLE-type questions with explanations • Numerous illustrations, diagrams, and tables • Easy-to-follow outline covering all USMLE-tested topics • A comprehensive examination V Ah, LIPPINCOTT -"*" WILLIAMS &WILKIN; mum IEEE mows IF 'IMP IMMO MINK I I. Key Physiology Topics for USMLE Step I Cell Physiology Transport mechanisms Ionic basis for action potential Excitation-contraction coupling in skeletal, cardiac, and smooth muscle Neuromuscular transmission Autonomic Physiology Cholinergic receptors Adrenergic receptors Effects of autonomic nervous system on organ system function Cardiovascular Physiology Events of cardiac cycle Pressure, flow, resistance relationships Frank-Starling law of the heart Ventricular pressure-volume loops Ionic basis for cardiac action potentials Starling forces in capillaries Regulation of arterial pressure (baroreceptors and renin-angiotensin II-aldosterone system) Cardiovascular and pulmonary responses to exercise Cardiovascular responses to hemorrhage Cardiovascular responses to changes in posture Respiratory Physiology Lung and chest-wall compliance curves Breathing cycle Hemoglobin-02 dissociation curve Causes of hypoxemia and hypoxia vq, P02, and P00 2 in upright lung V/Q defects Peripheral and central chemoreceptors in control of breathing Responses to high altitude Renal and Acid-Base Physiology Fluid shifts between body fluid compartments Starling forces across glomerular capillaries Transporters in various segments of nephron (Na Cl-, HCO 3-, H+, Kt and glucose) Effects of hormones on renal function Simple acid-base disorders Common mixed acid-base disorders Gastrointestinal Physiology Gastrointestinal hormones Salivary, gastric, pancreatic, and biliary secretions Digestion and absorption of carbohydrates, proteins, and lipids Endocrine and Reproductive Physiology Mechanisms of hormone action ADH actions and pathophysiology Thyroid: steps in synthesis, pathophysiology of hypo- and hyperthyroidism Adrenal cortex: hormone synthesis, pathophysiology of Addison's disease, Cushing's syndrome, and adrenogenital syndromes Insulin: secretion, insulin receptors and actions, type I and II diabetes mellitus PTH: actions, hyperparathyroidism, hypoparathyroidism, PTH-rp, pseudohypoparathryoidism Actions of testosterone and dihydrotestosterone Menstrual cycle Hormones of pregnancy Board Review Series Physiology Third Edition Board Review Series Physiology Third Edition Linda S. Costanzo, Ph.D. Professor of Physiology Medical College of Virginia Virginia Commonwealth University Richmond, Virginia 414VP.- —iv LIPPINCOTT WILLIAMS & WILKINS IIIP A Wolters Kluwer Company Philadelphia • Baltimore • New York • London Buenos Aires • Hong Kong • Sydney • Tokyo Editor: Neil Marquardt Development Editor: Bridget Hilferty Marketing Manager: Scott Lavine Production Editor: Jennifer Ajello Designer: Risa Clow Compositor: Peirce Graphic Services Printer: Data Reproductions Corporation Copyright 2003 Lippincott Williams & Wilkins 351 West Camden Street Baltimore, MD 21201 530 Walnut Street Philadelphia, PA 19106 All rights reserved. This book is protected by copyright. No part of this book may be reproduced in any form or by any means, including photocopying, or utilized by any information storage and retrieval system without written permission from the copyright owner. The publisher is not responsible (as a matter of product liability, negligence, or oth- erwise) for any injury resulting from any material contained herein. This publica- tion contains information relating to general principles of medical care that should not be construed as specific instructions for individual patients. Manufacturers' product information and package inserts should be reviewed for current informa- tion, including contraindications, dosages, and precautions. Printed in the United States of America First Edition, 1995 Second Edition, 1998 Library of Congress Cataloging-in-Publication Data is available: ISBN 0-7817-3919-5 The publishers have made every effort to trace the copyright holders for borrowed material. If they have inadvertently overlooked any, they will be pleased to make the necessary arrangements at the first opportunity. To purchase additional copies of this book, call our customer service department at (800) 638-3030 or fax orders to (301) 824-7390. International customers should call (301) 714-2324. Visit Lippincott Williams & Wilkins on the Internet: http:/lwww.LIVW.com. Lippincott Williams & Wilkins customer service representatives are available from 8:30 am to 6:00 pm, EST. 05 06 4 5 6 7 8 9 10 Dedication For Richard and for Dan and Rebecca Contents Preface ix Acknowledgments xi 1 Cell Physiology 1 I. Cell Membranes 1 II. Transport Across Cell Membranes 2 III. Osmosis 6 IV. Diffusion Potential, Resting Membrane Potential, and Action Potential 8 V. Neuromuscular and Synaptic Transmission 14 VI. Skeletal Muscle 18 VII. Smooth Muscle 23 VIII. Comparison of Skeletal Muscle, Smooth Muscle, and Cardiac Muscle 24 Review Test 26 2 Neurophysiology 35 I. Autonomic Nervous System 35 II. Sensory Systems 39 III. Motor Systems 53 IV. Higher Functions of the Cerebral Cortex 61 V. Blood-Brain Barrier and Cerebrospinal Fluid 62 VI. Temperature Regulation 63 Review Test 66 3 Cardiovascular Physiology 73 I. Circuitry of the Cardiovascular System 73 II. Hemodynamics 74 III. Cardiac Electrophysiology 79 IV. Cardiac Muscle and Cardiac Output 85 V. Cardiac Cycle 96 VI. Regulation of Arterial Pressure 98 VII. Microcirculation and Lymph 103 VIIL Special Circulations 105 IX. Integrative Functions of the Cardiovascular System: Gravity, Exercise, and Hemorrhage 109 Review Test 114 4 Respiratory Physiology 127 I. Lung Volumes and Capacities 127 IL Mechanics of Breathing 129 VII Viii / Physiology III. Gas Exchange 137 N. Oxygen Transport 139 V. CO2 Transport 143 VI. Pulmonary Circulation 144 VII. Ventilation/Perfusion Defects 147 VIII. Control of Breathing 148 IX. Integrated Responses of the Respiratory System 151 Review Test 153 5 Renal and Acid-Base Physiology 161 I. Body Fluids 161 II. Renal Clearance, Renal Blood Flow, and Glomerular Filtration Rate 166 III. Reabsorption and Secretion 170 IV 'Nisei Regulation 174 V. K+ Regulation 178 VI. Renal Regulation of Urea, Phosphate, Calcium, and Magnesium 182 VII. Concentration and Dilution of Urine 183 VIII. Renal Hormones 189 IX. Acid-Base Balance 189 X. Diuretics 200 XI. Integrative Examples 201 Review Test 204 6 Gastrointestinal Physiology 215 I. Structure and Innervation of the Gastrointestinal Tract 215 II. Regulatory Substances in the Gastrointestinal Tract 217 III. Gastrointestinal Motility 221 N. Gastrointestinal Secretion 226 V. Digestion and Absorption 238 Review Test 245 7 Endocrine Physiology 251 I. Overview of Hormones 251 II. Cell Mechanisms and Second Messengers 254 III. Pituitary Gland (Hypophysis) 258 IV. Thyroid Gland 264 V. Adrenal Cortex and Adrenal Medulla 269 VI. Endocrine Pancreas—Glucagon and Insulin 276 VII. Calcium Metabolism (Parathyroid Hormone, Vitamin D, Calcitonin) 280 VIII. Sexual Differentiation 285 IX. Male Reproduction 286 X. Female Reproduction 288 Review Test 294 Comprehensive Examination 301 Index 323 Preface The subject matter of physiology is the foundation of the practice of medicine, and a firm grasp of its principles is essential for the physician. This book is intended to aid the student preparing for the United States Medical Licensing Examination (USMLE) Step 1. It is a concise review of key physiologic principles and is intended to help the student recall material taught during the first and second years of medical school. It is not intended to substitute for comprehensive textbooks or for course syllabi, al- though the student may find it a useful adjunct to physiology and pathophysiology courses. The material is organized by organ system into seven chapters. The first chapter re- views general principles of cellular physiology. The remaining six chapters review the major organ systems—neurophysiology, cardiovascular, respiratory, renal and acid–base, and endocrine physiology. Difficult concepts are explained stepwise, concisely, and clearly, with appropriate il- lustrative examples and sample problems. Numerous clinical correlations are included so that the student can understand physiology in relation to medicine. An integrative approach is used, when possible, to demonstrate how the organ systems work together to maintain homeostasis. There are 131 illustrations and flow diagrams and 52 tables to help the student visualize the material quickly and to aid in long-term retention. Questions reflecting the content and format of USMLE Step 1 are included at the end of each chapter and in a Comprehensive Examination at the end of the book. These questions, many with clinical relevance, require problem-solving skills rather than straight recall. Clear, concise explanations accompany the questions and guide the stu- dent through the correct steps of reasoning. The questions can be used as a pretest to identify areas of weakness or as a posttest to determine mastery. Special attention should be given to the Comprehensive Examination, because its questions integrate several areas of physiology and related concepts of pathophysiology and pharmacology. New to this edition: • Addition of new figures and tables • Updated organization and text • Expanded coverage of respiratory and endocrine physiology • Increased emphasis on pathophysiology • Replacement of matching questions with A-type questions