Ca antagonists do not alter aldosterone secretion during established Na depletion
Johnson, E.I.; McDougall, J.G.; Coghlan, J.P.; Denton, D.A.; Hardy, K.J.; Scoggins, B.A.; Wright, R.D.
American Journal of Physiology 248(6 Pt 1): E676-E680
1985
ISSN/ISBN: 0002-9513 PMID: 2408478 Document Number: 261982
Conscious sheep with a single adrenal gland transplanted to the neck to allow access to the adrenal vasculature were used to study the effect of calcium antagonists on aldosterone secretion. All were depleted in sodium by uncompensated loss of parotid saliva. EDTA, verapamil, methoxyverapamil, nisoldipine, lanthanum, propylmethylenedioxyindene and ryanodine were infused on separate occasions in 3 or 4 increasing doses. All infusions were made to produce known concentrations directly into the adrenal arterial blood supply. None of these infusions had any significant effect on aldosterone secretion rate, cortisol secretion rate, and little or no effect on plasma Na, K or blood pressure. At high infusion rates some agents (verapamil, methoxyverapamil) caused tachycardia. Angiotensin II stimulation of aldosterone secretion was inhibited by verapamil and nisoldipine.