title: The spatial distribution of actin and mechanical cycle of myosin are different in right and left ventricles of healthy mouse hearts.
abstract: The contraction of the right ventricle (RV) expels blood into the pulmonary circulation, and the contraction of the left ventricle (LV) pumps blood into the systemic circulation through the aorta. The respective afterloads imposed on the LV and RV by aortic and pulmonary artery pressures create very different mechanical requirements for the two ventricles. Indeed, differences have been observed in the contractile performance between left and right ventricular myocytes in dilated cardiomyopathy, in congestive heart failure, and in energy usage and speed of contraction at light loads in healthy hearts. In spite of these functional differences, it is commonly believed that the right and left ventricular muscles are identical because there were no differences in stress development, twitch duration, work performance, or power among the RV and LV in dogs. This report shows that on a mesoscopic scale [when only a few molecules are studied (here three to six molecules of actin) in ex vivo ventricular myofibrils], the two ventricles in rigor differ in the degree of orientational disorder of actin within in filaments and during contraction in the kinetics of the cross-bridge cycle.
authors.affiliation: Department of Cell Biology and Center for Fluorescence Technology and Nanomedicine, University of North Texas Health Science Center , 3500 Camp Bowie Boulevard, Fort Worth, Texas 76107, United States.
authors.forename: J
authors.initials: J
authors.lastname: Nagwekar
authors.forename: D
authors.initials: D
authors.lastname: Duggal
authors.forename: R
authors.initials: R
authors.lastname: Rich
authors.forename: S
authors.initials: S
authors.lastname: Raut
authors.forename: R
authors.initials: R
authors.lastname: Fudala
authors.forename: I
authors.initials: I
authors.lastname: Gryczynski
authors.forename: Z
authors.initials: Z
authors.lastname: Gryczynski
authors.forename: J
authors.initials: J
authors.lastname: Borejdo
mesh_terms: D000199:Actins / Q000737:chemistry* / Q000378:metabolism*; D000818:Animals; D004285:Dogs; D005260:Female; D006352:Heart Ventricles / Q000378:metabolism*; D007700:Kinetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008955:Models, Cardiovascular; D008958:Models, Molecular; D020409:Molecular Motor Proteins / Q000737:chemistry / Q000378:metabolism; D009200:Myocardial Contraction; D009210:Myofibrils / Q000737:chemistry / Q000378:metabolism; D009218:Myosins / Q000737:chemistry* / Q000378:metabolism*; D014018:Tissue Distribution; D016276:Ventricular Function
chemical_list: D000199:Actins; D020409:Molecular Motor Proteins; D009218:Myosins