Skutella M, Rüegg U T
Pharmacology Group, School of Pharmacy, University of Lausanne, Switzerland.
Biochem Biophys Res Commun. 1996 Jan 26;218(3):837-41. doi: 10.1006/bbrc.1996.0149.
We demonstrate here that stimulated 45Ca2+ influx in A7r5 vascular smooth muscle cells induced either by receptor activation with [Arg]8 vasopressin or by the SR-Ca(2+)-ATPase inhibitor thapsigargin was increased more than threefold if cells were preloaded with the intracellular calcium chelator BAPTA (1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid). The increased influx is probably due to an attenuation of negative feedback of Ca2+ on its own entry accompanied by increased Ca2+ storage capacity of BAPTA-loaded cells leading to diminished cellular Ca2+ release. We propose that BAPTA preloading could be a useful approach to investigate receptor-induced Ca2+ influx.
我们在此证明，如果用细胞内钙螯合剂BAPTA（1,2-双（2-氨基苯氧基）乙烷-N,N,N',N'-四乙酸）预先加载A7r5血管平滑肌细胞，那么由[精氨酸]8血管加压素激活受体或由SR-Ca(2+)-ATP酶抑制剂毒胡萝卜素诱导的45Ca2+内流会增加三倍以上。内流增加可能是由于Ca2+对其自身进入的负反馈减弱，同时BAPTA加载细胞的Ca2+储存能力增加，导致细胞Ca2+释放减少。我们提出，预先加载BAPTA可能是研究受体诱导的Ca2+内流的一种有用方法。
