Regulation Of Cardiac Contractility

Author : R. John Solaro
Publisher : Biota Publishing
Page : 46 pages
File Size : 46,6 Mb
Release : 2011-04-01
Category : Medical
ISBN : 9781615041756

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Regulation of Cardiac Contractility by R. John Solaro Pdf

Contractility describes the relative ability of the heart to eject a stroke volume (SV) at a given prevailing afterload (arterial pressure) and preload (end-diastolic volume; EDV). Various measures of contractility are related to the fraction as the SV/EDV or the ejection fraction, and the dynamics of ejection as determined from maximum pressure rise in the ventricles or arteries or from aortic flow velocities determined by echocardiography. At the cellular level, the ultimate determinant of contractility is the relative tension generation and shortening capability of the molecular motors (myosin cross-bridges) of the sarcomeres as determined by the rates and extent of Ca activation, the turnover kinetics of the cross-bridges, and the relative Ca responsiveness of the sarcomeres. Engagement of the regulatory signaling cascades controlling contractility occurs with occupancy and signal transduction by receptors for neurohumors of the autonomic nervous system as well as growth and stress signaling pathways. Contractility is also determined by the prevailing conditions of pH, temperature, and redox state. Short-term control of contractility is fully expressed during exercise. In long-term responses to stresses on the heart, contractility is modified by cellular remodeling and altered signaling that may compensate for a time but which ultimately may fail, leading to disorders.

Author : R. John Solaro
Publisher : Morgan & Claypool Publishers
Page : 47 pages
File Size : 45,6 Mb
Release : 2011
Category : Medical
ISBN : 9781615041749

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Regulation of Cardiac Contractility by R. John Solaro Pdf

Contractility describes the relative ability of the heart to eject a stroke volume (SV) at a given prevailing afterload (arterial pressure) and preload (end-diastolic volume; EDV). Various measures of contractility are related to the fraction as the SV/EDV or the ejection fraction, and the dynamics of ejection as determined from maximum pressure rise in the ventricles or arteries or from aortic flow velocities determined by echocardiography. At the cellular level, the ultimate determinant of contractility is the relative tension generation and shortening capability of the molecular motors (myosin cross-bridges) of the sarcomeres as determined by the rates and extent of Ca activation, the turnover kinetics of the cross-bridges, and the relative Ca responsiveness of the sarcomeres. Engagement of the regulatory signaling cascades controlling contractility occurs with occupancy and signal transduction by receptors for neurohumors of the autonomic nervous system as well as growth and stress signaling pathways. Contractility is also determined by the prevailing conditions of pH, temperature, and redox state. Short-term control of contractility is fully expressed during exercise. In long-term responses to stresses on the heart, contractility is modified by cellular remodeling and altered signaling that may compensate for a time but which ultimately may fail, leading to disorders. Table of Contents: Introduction: Contractility and the Integrative Biology of the Myocardium / Control of Contractility Is at the Cellular Level of Organization / Left Ventricular Diastolic and Systolic Pressure, Ejection, and Relaxation Reflect Sarcomeric Mechanical Properties / Integration of Sarcomere Mechanics with Cardiac Function Clarifies the Meaning of Preload, Afterload, and Contractility / Pressure Volume Loops Provide a Quantification of Contractility / Phosphorylations of Regulatory Proteins in Excitation Contraction Coupling Modify Contractility by Controlling Cellular Ca + Fluxes, the Response of the Myofilaments to Ca +, and the Kinetics of the Cross-Bridge Cycle / Contractility May Be Altered by a Variety of Mechanisms Not Involving a Prominent Role for the Autonomic Nervous System / Cardiac Function Curves Provide a Compact Graphical Representation of Regulation of CO and SV / Heart Failure as a Failure of Contractility / References

Author : Donald Bers
Publisher : Springer Science & Business Media
Page : 427 pages
File Size : 46,5 Mb
Release : 2012-12-06
Category : Medical
ISBN : 9789401006583

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Excitation-Contraction Coupling and Cardiac Contractile Force by Donald Bers Pdf

How is the heartbeat generated? What controls the strength of contraction of heart muscle? What are the links between cardiac structure and function? How does our understanding of skeletal and smooth muscle and non-muscle cells influence our thinking about force development in the heart? Are there important species differences in how contraction is regulated in the heart? How do the new molecular data fit together in understanding the heart beat? What goes wrong in ischemia, hypertrophy, and heart failure? This book paints a modern `portrait' of how the heart works and in this picture the author shows a close-up of the structural, biochemical, and physiological links between excitation and contraction. The author takes the reader through a series of important, interrelated topics with great clarity and continuity and also includes many useful illustrations and tables. The book starts by considering the cellular structures involved in excitation-contraction coupling and then described the characteristics of the myofilaments as the end effector of excitation-contraction coupling. A general scheme of calcium regulation is described and the possible sources and sinks of calcium are discussed in simple, but quantitative terms. The cardiac action potential and its many underlying currents are reviewed. Then the characteristics of some key calcium transport systems (calcium channels, sodium/calcium exchange and SR calcium uptake and release) are discussed in detail. This is then built into a more integrated picture of calcium regulation in succeeding chapters by detailed discussions of excitation-calcium coupling mechanisms (in skeletal, cardiac, and smooth muscle), the interplay between calcium regulatory processes, and finally mechanisms of cardiac inotropy, calcium overload, and dysfunction (e.g., ischemia, hypertrophy, and heart failure). Excitation-Contraction Coupling and Cardiac Contractile Force – Second Edition is an invaluable source of information for anyone who is interested in how the heart beat is controlled and especially suited for students of the cardiovascular system at all levels from medical/graduate students through senior investigators in related fields.

Author : Michitoshi Inoue,Masatsugu Hori,Shoichi Imai,Robert M. Berne
Publisher : Springer Science & Business Media
Page : 330 pages
File Size : 43,9 Mb
Release : 2013-11-09
Category : Medical
ISBN : 9784431683674

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Regulation of Coronary Blood Flow by Michitoshi Inoue,Masatsugu Hori,Shoichi Imai,Robert M. Berne Pdf

Research centering on blood flow in the heart continues to hold an important position, especially since a better understanding of the subject may help reduce the incidence of coronary arterial disease and heart attacks. This book summarizes recent advances in the field; it is the product of fruitful cooperation among international scientists who met in Japan in May, 1990 to discuss the regulation of coronary blood flow.

Author : S. Sideman,Rafael Beyar
Publisher : Springer Science & Business Media
Page : 448 pages
File Size : 43,7 Mb
Release : 2012-12-06
Category : Medical
ISBN : 9789400949928

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Simulation and Imaging of the Cardiac System by S. Sideman,Rafael Beyar Pdf

The ultrasound velocity tomography allows measurement of cardiac geometries for various phases in the cardiac cycle. The present tomograph makes reconstruc tions at intervals of 20 ms. Because of a lack of clear (intramural) landmarks (except the roots of the papillairy muscle), it is difficult to pinpoint spatial trajectories of particular points in the heart. Therefore, a second method was developed of injecting radiopaque markers in the heart and following their motion patterns during the cardiac cycle with help of a biplane X-ray equipment. The data obtained with both methods can be implemented in our finite element model of the heart to compute intramural stresses and strains. The results obtained sofar with the extended Darcy equation to account for the interaction of blood rheology and tissue mechanics look promising. Further testing with more sophisticated subjects than mentioned in Figure 9 is required before it will be implemented in our finite element model of the heart. We conclude that analysis of regional cardiac function, including regional myocardial blood flow, requires still a major research effort but the results obtained sofar justify, to our opinion, a continuation in this direction. Acknowledgement The authors acknowledge Dr. C. Borst and coworkers for doing the animal experiments and prof. Van Campen and dr. Grootenboer for their participation is some aspects of this work.

Author : Richard Nathan
Publisher : Elsevier
Page : 340 pages
File Size : 48,9 Mb
Release : 2012-12-02
Category : Medical
ISBN : 9780323155182

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Cardiac Muscle: The Regulation Of Excitation And Contraction by Richard Nathan Pdf

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.

Author : David Jordan,Janice Marshall
Publisher : Ashgate Publishing
Page : 159 pages
File Size : 55,6 Mb
Release : 1995
Category : Medical
ISBN : 1855780240

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Cardiovascular Regulation by David Jordan,Janice Marshall Pdf

The Studies in Physiology series provides a concise introduction to developments in complex areas of physiology for a wide audience. Published on behalf of the Physiology Society, Cardiovascular Regulation provides an up-to-date account of our current understanding of the control of the cardiovascular system that is not covered by existing textbooks. Both students and lecturers of cardiovascular and exercise physiology, medicine, dentistry and biomedical sciences will find this book informative and easy to read. Each chapter has numerous summary boxes. 'Essential reading' suggestions provide additional reading for undergraduates and the suggestions for 'Further reading' cover the subject to postgraduate level.

Author : Roland N. Pittman
Publisher : Biota Publishing
Page : 117 pages
File Size : 47,9 Mb
Release : 2016-08-18
Category : Medical
ISBN : 9781615047215

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Regulation of Tissue Oxygenation, Second Edition by Roland N. Pittman Pdf

This presentation describes various aspects of the regulation of tissue oxygenation, including the roles of the circulatory system, respiratory system, and blood, the carrier of oxygen within these components of the cardiorespiratory system. The respiratory system takes oxygen from the atmosphere and transports it by diffusion from the air in the alveoli to the blood flowing through the pulmonary capillaries. The cardiovascular system then moves the oxygenated blood from the heart to the microcirculation of the various organs by convection, where oxygen is released from hemoglobin in the red blood cells and moves to the parenchymal cells of each tissue by diffusion. Oxygen that has diffused into cells is then utilized in the mitochondria to produce adenosine triphosphate (ATP), the energy currency of all cells. The mitochondria are able to produce ATP until the oxygen tension or PO2 on the cell surface falls to a critical level of about 4–5 mm Hg. Thus, in order to meet the energetic needs of cells, it is important to maintain a continuous supply of oxygen to the mitochondria at or above the critical PO2 . In order to accomplish this desired outcome, the cardiorespiratory system, including the blood, must be capable of regulation to ensure survival of all tissues under a wide range of circumstances. The purpose of this presentation is to provide basic information about the operation and regulation of the cardiovascular and respiratory systems, as well as the properties of the blood and parenchymal cells, so that a fundamental understanding of the regulation of tissue oxygenation is achieved.

Author : J R Levick
Publisher : Butterworth-Heinemann
Page : 288 pages
File Size : 47,6 Mb
Release : 2013-10-22
Category : Medical
ISBN : 9781483183848

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An Introduction to Cardiovascular Physiology by J R Levick Pdf

An Introduction to Cardiovascular Physiology is designed primarily for students of medicine and physiology. This introductory text is mostly didactic in teaching style and it attempts to show that knowledge of the circulatory system is derived from experimental observations. This book is organized into 15 chapters. The chapters provide a fuller account of microvascular physiology to reflect the explosion of microvascular research and include a discussion of the fundamental function of the cardiovascular system involving the transfer of nutrients from plasma to the tissue. They also cover major advances in cardiovascular physiology including biochemical events underlying Starling's law of the heart, nonadrenergic, non-cholinergic neurotransmission, the discovery of new vasoactive substances produced by endothelium and the novel concepts on the organization of the central nervous control of the circulation. This book is intended to medicine and physiology students.

Author : Albert Dahan,Luc Teppema,Johannes H.G.M. van Beek
Publisher : Springer Science & Business Media
Page : 149 pages
File Size : 42,6 Mb
Release : 2011-06-27
Category : Medical
ISBN : 9789401151290

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Physiology And Pharmacology of Cardio-Respiratory Control by Albert Dahan,Luc Teppema,Johannes H.G.M. van Beek Pdf

On 15 November 1997, the first international symposium "Neural and Chemical Control of Breathing: Pharmacological and Clinical Aspects" was held at Leiden University Medical Center on the occasion of the retirement of one of the members of the Control of Breathing Research Group of the Departments of Physiology and Anesthesiology, Dr. Aad Berkenbosch. Among others, Dr. Berkenbosch, played an important role in this research group, which made a large and significant contribution to scientific research on the regulation of breathing. This book presents the proceedings of that meeting together with papers of several authors who have strong bonds with the Leiden Departments of Physiology and Anesthesiology. All studies represent state of the art work on the subject of respiratory control and cardiovascular medicine, with emphasis on the physiological, pharmacological and anesthesiological aspects of both fields. The book is divided in several sections: Oxygen Physiology. Prof. John Severinghaus presents among other things his ideas on oxygen sensing and high altitude related diseases. Prof. Honda gives results from studies in a unique set of subjects without carotid bodies. The findings of Honda's group support the idea that an intact hypoxic drive from the carotid bodies is necessary for the generation of central hypoxic depression. Dr. Hans van Beek discusses the effects of hypoxia and hypercapnia on cardiac contractility in animal models. Prof. Oeseburg demonstrates the feasibility of Near Infra Red Oximetry for monitoring tissue oxygenation in patients. Central Chemoreception.

Author : J. Gordon Betts,Peter DeSaix,Jody E. Johnson,Oksana Korol,Dean H. Kruse,Brandon Poe,James A. Wise,Mark Womble,Kelly A. Young
Publisher : Unknown
Page : 0 pages
File Size : 42,6 Mb
Release : 2013-04-25
Category : Electronic
ISBN : 1947172808

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Anatomy and Physiology by J. Gordon Betts,Peter DeSaix,Jody E. Johnson,Oksana Korol,Dean H. Kruse,Brandon Poe,James A. Wise,Mark Womble,Kelly A. Young Pdf

Author : Richard E. Klabunde
Publisher : Lippincott Williams & Wilkins
Page : 689 pages
File Size : 48,9 Mb
Release : 2020-12-01
Category : Medical
ISBN : 9781975150099

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Cardiovascular Physiology Concepts by Richard E. Klabunde Pdf

Praised for its concise coverage, this highly accessible monograph lays a foundation for understanding the underlying concepts of normal cardiovascular function and offers a welcome alternative to a more mechanistically oriented approach or an encyclopedic physiology text. Clear explanations, ample illustrations and engaging clinical cases and problems provide the perfect guidance for self-directed learning and prepare you to excel in clinical practice.

Author : Cesare Terracciano,Samuel Guymer
Publisher : Springer Nature
Page : 236 pages
File Size : 42,7 Mb
Release : 2019-11-01
Category : Science
ISBN : 9783030242190

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Heart of the Matter by Cesare Terracciano,Samuel Guymer Pdf

This textbook introduces readers to the scientific basics of cardiovascular medicine and biology. It covers not only developmental but also cellular and molecular aspects of normally functioning vasculature and the heart; importantly, it also addresses the mechanisms leading to and involved in specific cardiovascular diseases. Though the main emphasis is on novel therapies and potential therapeutic targets, specific controversial topics like cardiac remodeling and regenerative capacities are also addressed. All chapters were written by lecturers from the Imperial College London, in collaboration with their students from the College’s BSc Programme in Medical Sciences with Cardiovascular Science. Bridging the gap between clinics and basic biology, the book offers a valuable guide for medical students, and for Master and PhD students in Cardiovascular Biomedicine.

Author : Irving H. Zucker,Joseph P. Gilmore
Publisher : CRC Press
Page : 1088 pages
File Size : 42,5 Mb
Release : 2020-02-03
Category : Medical
ISBN : 9781000725384

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Reflex Control of the Circulation by Irving H. Zucker,Joseph P. Gilmore Pdf

Reflex Control of the Circulation presents an interdisciplinary discussion of concepts in the reflex control of circulation. This volume describes aspects of autonomic receptor physiology, central pathways of reflex control, the electrophysiology of cardiovascular afferents, the interaction between reflexes, the autonomic control of regional blood flows, the autonomic control of fluid and electrolyte balance, and neurohumoral control of the circulation through normal and pathological states (e.g., hypertension, congestive heart failure). In addition, the regulation of regional blood flow during exercise and developmental aspects of reflex control are examined. Any researcher interested in the autonomic system and its role in circulation will find this book fascinating reading.

Author : David C. Warltier
Publisher : Lippincott Williams & Wilkins
Page : 404 pages
File Size : 49,9 Mb
Release : 1995
Category : Medical
ISBN : UOM:39015034250566

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Ventricular Function by David C. Warltier Pdf