A dominant role of cardiac molecular motors in the intrinsic regulation of ventricular ejection and relaxation.
Molecular motors housed in myosins of the thick filament react with thin-filament actins and promote force and shortening in the sarcomeres. However, other actions of these motors sustain sarcomeric activation by cooperative feedback mechanisms in which the actin-myosin interaction promotes thin-filament activation. Mechanical feedback also affects the actin-myosin interaction. We discuss current concepts of how these relatively under-appreciated actions of molecular motors are responsible for modulation of the ejection time and isovolumic relaxation in the beating heart.
Hinken
Aaron C
AC
Department of Physiology and Biophysics and Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, IL, USA.
Solaro
R John
RJ
D000199:Actins / Q000502:physiology; D000818:Animals; D024722:Cardiac Myosins / Q000502:physiology; D006321:Heart / Q000502:physiology*; D006801:Humans; D009200:Myocardial Contraction / Q000502:physiology*; D012518:Sarcomeres / Q000502:physiology; D013318:Stroke Volume / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology
D000199:Actins; D024722:Cardiac Myosins