The effects of corticosteroids on the reduction of α-adrenoceptor blockade produced by β-adrenoceptor blocking agents

Abstract

The inhibition of the pressor effects of noradrenaline by phenoxybenzamine was reduced by propranolol and sotalol in the normal and acutely adrenalectomized, but not in the chronically adrenalectomized, rat. The administration of a glucocorticoid, but not a mineralocorticoid, to the chronically adrenalectomized rat, produced a preparation in which the phenoxybenzamine-produced α-adrenoceptor blockade was reduced by the β-adrenoceptor blocking agents, demonstrating that this action is glucocorticoid-dependent.