期刊
PHARMACOLOGY
卷 81, 期 4, 页码 325-332出版社
KARGER
DOI: 10.1159/000121335
关键词
astragaloside IV; intracellular calcium; sarcoplasmic reticulum; hypoxia/reoxygenation
Although astragaloside IV, a saponin isolated from Astragalus membranaceus, has been shown to protect the myocardium against ischemia/reperfusion injury, its effect on the status of sarcoplasmic reticulum (SR) Ca2+ transport in the injured myocardium remains largely unknown. In this study, we investigated whether in cultured cardiomyocytes subjected to hypoxia and reoxygenation (H/R) administration of astragaloside IV during H/R attenuates the myocardial cell injury and prevents changes in Ca2+ handling activities and gene expression of SR Ca2+ pump. Cultured cardiomyocytes from neonatal rats were exposed to 6 h of hypoxia followed by 3 h of reoxygenation. Myocyte injury was determined by the release of cardiac troponin I in supernatant. Astragaloside IV significantly inhibited cardiac troponin I release after H/R in a dose-dependent manner. The diastolic [Ca2+](i) measured with Fura-2/AM was significantly increased after reoxygenation. Astragaloside IV prevented the rise of diastolic [Ca2+](i) and the depression of caffeine-induced Ca2+ transients caused by H/R. Furthermore, the observed depressions in SR Ca2+-ATPase activity as well as the mRNA and protein expression of SR Ca2+-ATPase in hypoxic-reoxygenated cardiomyocytes were attenuated by astragaloside IV treatment. These results suggest that the beneficial effect of astragaloside IV in H/R-induced injury may be related to normalization of SR Ca2+ pump expression and, thus, may prevent the depression in SR Ca2+ handling. Copyright (c) 2008 S. Karger AG, Basel.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据