细胞外5'-三磷酸腺苷对新鲜分离的成年大鼠心肌细胞钙离子外流的影响。

Effect of extracellular adenosine 5'-triphosphate on Ca2+ efflux from freshly isolated adult rat cardiomyocytes.

作者信息

Hori T, offhizumi M, Kitagawa T, Chikugo F, Kawahito T, Katoh I, Houchi H, Oka M

机构信息

Department of Cardiovascular Surgery and Pharmacology, School of Medicine, University of Tokushima, Japan.

出版信息

Life Sci. 1996;58(11):PL217-22. doi: 10.1016/0024-3205(96)00040-9.

DOI:10.1016/0024-3205(96)00040-9

PMID:8786691

Abstract

The effect of extracellular adenosine 5'-triphosphate (ATP) on Ca2+ efflux from freshly isolated adult rat cardiomyocytes was examined. ATP stimulated the efflux of 45Ca2+ from the cells in a concentration-dependent manner (0.01-1 mM). The 45Ca2+ efflux from the cells was also stimulated by adenosine-5'-O-(3-thiotriphosphate)(ATP-gammas) and alpha,beta-methylene-ATP and adenosine 5'-diphosphate, but not by adenosine 5'-monophosphate and adenosine. The ATP-stimulated 45Ca2+ efflux was not affected by deprivation of the extracellular Ca2+, but was dependent on the presence of extracellular Na+. These results indicate that ATP stimulates extracellular Na+-dependent 45Ca2+ efflux from freshly isolated adult rat cardiomyocytes, probably through its stimulatory effect on the plasma membrane P2 purinoceptors which may couple to Na+/Ca2+ exchange.

摘要

研究了细胞外5'-三磷酸腺苷（ATP）对新鲜分离的成年大鼠心肌细胞Ca2+外流的影响。ATP以浓度依赖性方式（0.01 - 1 mM）刺激细胞内45Ca2+的外流。细胞内45Ca2+的外流也受到5'-O-(3-硫代三磷酸)腺苷（ATP-γS）、α,β-亚甲基-ATP和二磷酸腺苷的刺激，但不受一磷酸腺苷和腺苷的刺激。ATP刺激的45Ca2+外流不受细胞外Ca2+缺失的影响，但依赖于细胞外Na+的存在。这些结果表明，ATP可能通过对质膜P2嘌呤受体的刺激作用来刺激新鲜分离的成年大鼠心肌细胞的细胞外Na+依赖性45Ca2+外流，而该受体可能与Na+/Ca2+交换偶联。