{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T15:01:47Z","timestamp":1790866907054,"version":"4.1.0"},"reference-count":0,"publisher":"American Physiological Society","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["American Journal of Physiology-Cell Physiology"],"published-print":{"date-parts":[[1995,4,1]]},"abstract":"<jats:p> Using Ca2+ channel blockers with different specificities for L- and T-type Ca2+ channels, we have investigated the roles of these two channel types in K(+)-induced aldosterone secretion. In whole cell voltage-clamp experiments, the spider toxin omega-agatoxin-IIIA (omega-Aga-IIIA) completely blocks L-type Ca2+ channels but has no effect on T-type Ca2+ channels. In contrast, Ni2+ and 1,4-dihydropyridines block both L- and T-type Ca2+ channels. Secretion induced by 7 mM extracellular K+ concentration ([K+]o) is unaffected by omega-Aga-IIIA but is strongly inhibited by Ni2+ or the 1,4-dihydropyridine, nitrendipine. This suggests that physiological increases in [K+]o stimulate aldosterone secretion primarily by enhancing Ca2+ entry through T-type Ca2+ channels. Surprisingly, secretion induced by 60 mM [K+]o is enhanced by omega-Aga-IIIA or Ni2+ and is inhibited by the L-type Ca2+ channel activator BAY K 8644. Nitrendipine (1 nM) also stimulates such secretion, although higher concentrations are inhibitory (concentration inhibiting 50% of maximal response approximately 30 nM). If extracellular Ca2+ concentration is reduced from 1.25 to 0.5 mM, secretion induced by 60 mM [K+]o is enhanced, and Ni2+ or low nitrendipine become inhibitory. Together, these results that L-type Ca2+ currents can reduce steroidogenesis and that the role of these currents was previously misconstrued because 1,4-dihydropyridines modify secretion by multiple mechanisms. Thus Ca2+ entry can function as a negative modulator of steroid secretion. <\/jats:p>","DOI":"10.1152\/ajpcell.1995.268.4.c985","type":"journal-article","created":{"date-parts":[[2017,12,24]],"date-time":"2017-12-24T18:39:42Z","timestamp":1514140782000},"page":"C985-C992","source":"Crossref","is-referenced-by-count":45,"title":["Voltage-gated calcium currents have two opposing effects on the secretion of aldosterone"],"prefix":"10.1152","volume":"268","author":[{"given":"P. Q.","family":"Barrett","sequence":"first","affiliation":[{"name":"Department of Pharmacology, University of Virginia, Charlottesville22908, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"E. A.","family":"Ertel","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, University of Virginia, Charlottesville22908, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M. M.","family":"Smith","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, University of Virginia, Charlottesville22908, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. J.","family":"Nee","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, University of Virginia, Charlottesville22908, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C. J.","family":"Cohen","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, University of Virginia, Charlottesville22908, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","container-title":["American Journal of Physiology-Cell Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.physiology.org\/doi\/pdf\/10.1152\/ajpcell.1995.268.4.C985","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,6,17]],"date-time":"2024-06-17T19:37:41Z","timestamp":1718653061000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.physiology.org\/doi\/10.1152\/ajpcell.1995.268.4.C985"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1995,4,1]]},"references-count":0,"journal-issue":{"issue":"4","published-print":{"date-parts":[[1995,4,1]]}},"alternative-id":["10.1152\/ajpcell.1995.268.4.C985"],"URL":"https:\/\/doi.org\/10.1152\/ajpcell.1995.268.4.c985","relation":{},"ISSN":["0363-6143","1522-1563"],"issn-type":[{"value":"0363-6143","type":"print"},{"value":"1522-1563","type":"electronic"}],"subject":[],"published":{"date-parts":[[1995,4,1]]}}}