期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1972
卷号：69
期号：2
页码：463-465
DOI：10.1073/pnas.69.2.463
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The positive inotropic action of glucagon on the cat heart is dependent upon the extracellular Ca concentration. The inotropic effect is proportionately greater, the lower the concentration of Ca in the perfusate (above zero, at which glucagon is without significant effect). Nevertheless, Ca influx (as measured with 45Ca) into the myocardium is not demonstrably influenced by glucagon, except at 0.09 mM Ca, where the interpretation of the effect is complicated by the fact that there is mechanical asystole at that Ca concentration in the absence of glucagon, while excitation-contraction coupling still occurs when the hormone is added. The possibility is suggested that glucagon may influence intracellular movement of Ca, even when its transmembrane movement is affected only slightly.
关键词：calcium fluxes ; myocardial function ; asystole ; membrane transport ; cat
