Endothelin-1 stimulates sodium-dependent calcium efflux from bovine adrenal chromaffin cells in culture

摘要

The effect of endothelin(ET)-1 on Ca~2+ efflux from cultured bovine adrenal chromaffin cells was examined. ET-1(10~-7 M) significantly increased intracellular free Ca~2+ level ([Ca~2+]I), ~45Ca~2+ uptake and catecholamine secretion in the cells. ET-1 stimulated the efflux of ~45Ca~2+ from the cells preloaded with ~45Ca~2+ in a concentration- Dependent manner (10~-9 -10~-7 M). This stimulatory effect was inhibited by ET_B receptor antagonist BQ788, but not by ET_A receptor antagonist BQ123. Selective ET_B receptor agonists Suc-[Glu~9, Ala~11,15]- ET-1 and sarafotoxin S6c (SRTX)also stimulated ~45Ca~2+ efflux from the cells.