Abstract

The role of the renal beta-1 and beta-2 adrenoceptor subtypes in renin release was evaluated in anesthetized dogs. The renal baroreceptor and macula densa mechanisms of renin release were inhibited by pretreatment with indomethacin (8 mg/kg i.v.). Thus, the beta adrenergic mechanism of renin release was functionally isolated. Intrarenal infusion of isoproterenol at two infusion rates elicited local renal effects and systemic effects at the low and high infusion rates, respectively. Renin secretion was stimulated at both infusion rates. Isoproterenol elicited a significant renin release in the presence of beta-1 adrenoceptor blockade with atenolol and in the presence of selective beta-2 adrenoceptor blockade with IPS-339. In addition, intrarenal infusion of albuterol, a selective beta-2 adrenoceptor agonist, stimulated renin release in the absence and presence of atenolol. These results lead to the conclusion that beta adrenergically mediated release of renin in the dog is not confined to either the beta-1 or beta-2 adrenoceptor subtypes.