Extracellular ATP stimulates estradiol secretion in rat Sertoli cells in vitro: modulation by external sodium

[摘要] In this study, we examined the effects of extracellular ATP (ATPc) on [Ca2+](i), [Na+](i), plasma membrane potential changes and estradiol secretion in rat Sertoli cells. ATPe caused a rapid rise of [Ca2+](i) with an initial spike followed by a long lasting plateau. The first rapid spike was dependent on the release of Ca2+ from internal stores as it also occurred in Ca2+-free medium while the long lasting plateau phase was dependent on Ca2+ influx from the external medium. ATPe stimulated a rapid plasma membrane depolarization that was dependent on an influx of Na+ from the external medium as demonstrated by plasma membrane potential monitoring in Na+-free medium and by [Na+](i) measurement with the Na+-sensitive fluorescent dye SBFI. ATPe stimulated estradiol secretion in a dose dependent manner and was fully dependent on the presence of Na i in the external medium while the presence of Ca2+ was not necessary. Among the different nucleotides tested, only ATP, ATP-5'-[gamma -thio]triphosphate, UTP, alpha,beta -methylene-ATP were effective in stimulating estradiol secretion. These results demonstrate that rat Sertoli cells possess P2-purinergic receptors belonging to the P2X and P2Y subfamily which activation induces [Ca2+](i) and [Na+](i) rise and Na+-dependent plasma membrane depolarization leading to estradiol secretion. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

[发布日期] 2001-06-10

[效力级别]  Proceedings Paper

[关键词] ATP;purinergic receptors;Sertoli;calcium;sodium;estradiol