Azolimine: a nonsteroidal antagonist of the effects of mineralocorticoids on renal electrolyte excretion.

Azolimine, CL 90,748, an imidazolidinone, displayed the capacity to antagonize the effects of mineralocorticoids on renal electrolyte excretion in several animal models. Although large doses of azolimine produced natriuresis in adrenalectomized rats in the absence of exogenous mineralocorticoid, its effectiveness was greater in the presence of a steroid agonist. However, in conscious dogs given an infusion of saline plus dextrose, azolimine was only effective when desoxycorticosterone (DCA) was administered. The drug, therefore, may not be a pure competitive antagonist of mineralocorticoid, but its greater efficacy in the presence of mineralocorticoid distinguishes it from noncompetitive mineralocorticoid antagonists as amiloride and triamterene. Azolimine significantly improved the urinary Na/K ratio when used in combination with thiazides, furosemide and other classical diuretics both in adrenalectomized, desoxycorticosterone-treated rats and in sodium-deficient rats.