Sources of Ca~2+ in relation to generation of acetylcholine- induced endothelium-dependent hyperpolarization in rat mesenteric artery

摘要

These results indicate that the ACh-induced release of EDHF from endothelial cells of rat mesenteric artery is possibly initiated by Ca~2+ release from inositol 1, 4, 5-trisphosphate(IP_3)-sensitive Ca~2+ pool as a consequence of stimulation of phospholipid hydrolysis due to phospholipase C activation, and maintained by Ca~2+ influx via a Ni~2+ -and Mn~2+ -sensitive pathway distinct from L-type Ca~2+ channels. The Ca~2+ -influx mechanism seems to be activated following IP_3-induced depletion of the pool.