Effect of alpha- and beta-Adrenergic Blocking Agents on the Renin Response to Hypoglycemia and Epinephrine in Dogs

In dogs treated with the β-adrenergic blocking agent, propranolol, there was almost complete inhibition of the increase in renin secretion produced by insulin-induced hypoglycemia. In dogs treated with the α-adrenergic blocking agent, phenoxybenzamine, there was a slight potentiation of the renin response to hypoglycemia. The increase in renin secretion produced by infusing epinephrine was slightly potentiated by phenoxybenzamine, whereas it was abolished when dogs that had received phenoxybenzamine were also given propranolol. The data strongly suggest that epinephrine stimulates renin secretion via a β-adrenergic receptor mechanism, and that the stimulatory effect of hypoglycemia is mediated, at least in part, via the increase in circulating epinephrine that it produces.