Hyperglycemic effect of hydralazine in rats.

The effect of hydralazine in the alteration of blood sugar, tissue glycogen and blood cAMP levels in rats were investigated. Hydralazine was found to increase blood sugar level in intact rats when administered i.p. On the other hand, this hyperglycemia was partially blocked either by the treatment of intact rats with propranolol, beta-adrenergic blocker, or by adrenalectomy. Hydralazine treatment increased blood cAMP level, leading to the hyperglycemia, because pretreatment with phentolamine partially blocked the hydralazine-induced hyperglycemia.