| Autor: |
Xiao-Le Xu, Xiang-Jian Chen, Hui Ji, Ping Li, Yun-Yun Bian, Di Yang, Jin-Dan Xu, Zhi-Ping Bian, Ji-Nan Zhang |
| Předmět: |
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| Zdroj: |
Pharmacology; 2008, Vol. 81 Issue 4, p325-332, 8p, 1 Diagram, 5 Graphs |
| Abstrakt: |
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 © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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