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Cardiac Muscle: The Regulation of Excitation and Contraction is a 12-chapter text that covers the research studies on characterizing the ionic and molecular mechanisms that regulate excitation and contraction of cardiac muscle. This book describes first the ionic currents underlying diastolic depolarization and pacing of the heart. The discussions then shift to the mechanisms of action of calcium-channel antagonists; the regulation of calcium influx by indigenous factors, such as voltage- or calcium-mediated inactivation; the identification of fixed negative charges on the surface of the sarcolemma; and the regulation of gating and permeability of ion channels by these charges. These topics are followed by examining the molecular and ionic mechanisms that underlie the electrophysiologic actions of adrenergic and cholinergic neurotransmitters and peptide hormones. This text further explores the theoretical and experimental studies of the sodium-calcium exchange process, its stoichiometry, and how the exchanger might contribute to current flow during or after the action potential. Other chapters consider the mechanism of twitch and tonic tension regulation by cardiac glycosides and intracellular sodium and how toxic concentrations induce cardiac arrhythmias. A chapter highlights the identification of sarcolemmal binding sites for calcium, the likelihood that such binding or the release of calcium from the sarcoplasmic reticulum plays a role in the regulation of contraction and the release of calcium from the sarcoplasmic reticulum. The remaining chapters deal with the structural similarities among calcium-binding proteins of the contractile apparatus and the calcium channel, and the regulation of contraction by calcium-binding proteins. Physiologists, pathophysiologists, clinicians, researchers, and students who are interested in heart's function will find this book invaluable.
Language
Place of publication
Publishing group
Elsevier Science & Techn.
ISBN-13
978-0-323-15518-2 (9780323155182)
Schweitzer Classification
Contributors Preface 1. Ionic Currents Underlying Cardiac Pacemaker Activity: A Summary of Voltage-Clamp Data from Single Cells I. Foreword II. Introduction III. Methods IV. Results V. Summary References 2. Inactivation and Modulation of Cardiac Ca Channels I. Introduction II. Inactivation of Cardiac Calcium Channels: Voltage- and Calcium-Mediated Mechanisms III. State-Dependent Modulation of Ca-Channel Current IV. Summary References3. Negative Surface Charge: Its Identification and Regulation of Cardiac Electrogenesis I. Introduction II. Fixed Negative Charges on the Surface of Cardiac Myocytes III. Identification of the Negative Surface Charge IV. Summary References 4. Mechanisms of ß-Adrenergic and Cholinergic Control of Ca and K Currents in the Heart I. Introduction II. Action Potential and Membrane Current III. ß-Adrenergic Stimulation IV. Single-Ca-Channel Activity, Adrenaline, and cAMP V. Mechanism of Action of Acetylcholine VI. The Second Muscarinic Response VII. Summary and Perspectives for Future Research References 5. Modulation of Cell Electrical Properties by Peptide Hormones I. Introduction II. The Brain-Gut Peptides III. The Polypeptide Growth Factors IV. Mechanism of Peptide Hormone Action V. Conclusions and Future Research Directions References 6. Sodium-Calcium Exchange and Its Role in Generating Electric Current I. Introduction II. Equilibrium and Steady-State Theory of the Sodium-Calcium Exchange Process III. Theory of Transient Changes in the Sodium-Calcium Exchange Process IV. The Calcium Transient V. The Sodium-Potassium Exchange Process VI. Variation of E-NaCa during Activity VII. How Much Current Should the Carrier Generate? VIII. Time Constant for Exchange Process IX. Ionic Currents That Might be Attributed to Sodium-Calcium Exchange X. Relation between Slow Components of isi and the Transient Inward Current, iT1 XI. Artificially Induced Slow Inward Current XII. Current-Voltage Relations for [Ca]i-Induced Variations in i-NaCa XIII. Conclusions References 7. Some Experimental Studies of Na-Ca Exchange in Heart Muscle I. Introduction II. Experimental Studies III. Discussion IV. Summary References 8. The Regulation of Tension in Heart Muscle by Intracellular Sodium I. Introduction II. Methods III. Results and Discussion IV. Conclusions References 9. Cardiac Glycosides: Regulation of Force and Rhythm I. Introduction II. Cardiac Glycosides and the Regulation of Contractile Force III. Cardiac Glycosides and the Regulation of Rhythm IV. Conclusions References10. Calcium at the Sarcolemma: Its Role in Control of Myocardial Contraction I. Introduction II. Extracellular Calcium III. Sarcolemmal Calcium Binding IV. Role of Phospholipid in Ca Binding V. Relationship of Ca Binding to Primary Alteration in Transsarcolemmal Flux VI. Present Concepts VII. Conclusions References11. Release of Calcium from the Sarcoplasmic Reticulum I. Introduction II. Evidence for and against a Release of Calcium from the Sarcoplasmic Reticulum during Cardiac Excitation-Contraction Coupling III. Hypothesis of Calcium-Induced Release of Calcium from the Sarcoplasmic Reticulum IV. Hypothesis of Depolarization-Induced Release of Calcium from the Sarcoplasmic Reticulum V. Hypothesis of Sodium-Induced Release of Calcium from the Sarcoplasmic Reticulum VI. Hypothesis of Release of Calcium from the Sarcoplasmic Reticulum Induced by a Change in pH VII. Hypothesis of Release of Calcium Induced by Movement of Transverse Tubular or Sarcolemmal Charged Particles Linked Mechanically to Sites in the Sarcoplasmic Reticular Membrane VIII.