KAPOPORT, STANLEY I., AND JEANNETTE M. BIDINGER. Eject of stretch on contractility and ionic contents of the sartorius muscle of Rana pipiens. Am. J. Physiol. 226(Z) : 452-457’ 1974.-When sartorius muscles of frogs are soaked in Ringer at room temperature, they gain Na, lose K, and lose contractility with time. These changes are retarded by stretching the muscles to ZO-30Y0 of their rest length...

We injected neuroexcitatory and neuroinhibitory agents into the depressor region of the caudal ventrolateral medulla of anesthetized rabbits and determined the effect on arterial pressure, myocardial contractility, cardiac output, and plasma catecholamines and neuropeptide Y. Brief excitation of the sympathoinhibitory neurons with medullary injection of L-glutamate reduced arterial pressure, pe...

Limited data are available concerning left ventricular contractility and contractile reserve in the chronically denervated, transplanted human heart. This is primarily because of the inability of traditional tests of left ventricular performance to distinguish changes in contractility from alterations in ventricular loading conditions. In this study, load-independent end-systolic indexes of lef...

Background. Although a-adrenergic receptors are present in both normal and failing human left ventricular myocardium and mediate a positive inotropic effect in several other species, it is not known whether stimulation of myocardial ca-adrenergic receptors exerts a positive inotropic effect or contributes to basal contractile state in vivo in humans. Methods and Results. We studied 15 patients ...

This study is performed to investigate the effect of Fontan operations on cardiac contractility. Investigation of articles about the contractility in Fontan published in PubMed up to now revealed that the measurement of contractility values did not include the rudimentary ventricle. Connections between right atrium and right ventricle as well as right atrium and pulmonary artery were studied in...

Chronic atrial fibrillation represents one of the main risk factors for the occurrence of thromboembolic events. At present it is clear that thrombus formation is triggered, not only by irregular rhythm, but also by reduced intrinsic atrial contractility. Apart from the thromboembolic risk, reduced atrial contractility might contribute to reduced cardiac output in patients with ventricular hear...

Contractility in fibers can arise from changes of macromolecular conformation caused by changes in some thermodynamic variable such as temperature, pH, or solvent composition. Illustrations are given of contractile processes in fibers and of changes in macromolecular conformation in dilute solution. These may involve order-disorder transitions, e.g. of the type exhibited by the helix-coil trans...

CONTENTS 3.1 Scope ............................................................................................................. 68 3.2 Left Ventricular Shape Factor Based Contractility Index .................... 68 3.2.1 LV Model Geometry Development ............................................. 69 3.2.2 Determination of LV Model Wall Stress..................................... 70 3.2.3 Normal...

BACKGROUND Our laboratory reported that male mice with cardiomyocyte-selective knockout of the prostaglandin E2 EP4 receptor sub-type (EP4 KO) exhibit reduced cardiac function. Gene array on left ventricles (LV) showed increased fractalkine, a chemokine implicated in heart failure. We therefore hypothesized that fractalkine is regulated by PGE2 and contributes to depressed contractility via alt...