metiamide and Shock

The present study was undertaken to determine the effect of exogenous histamine and histamine blockers on blood glucose and hepatic glycogen in the rat. Forty-one nonfasted male Sprague-Dawley rats that had been anesthetized with intraperitoneal injections of urethane were injected intravenously (femoral) with histamine (10 mg/kg) five minutes after pretreatment with Ringer's solution (control), diphenhydramine (1 mg/kg) (H-1 blocker); metiamide (1 mg/kg) (H-2 blocker); or a combination of these blockers. Mean arterial pressure (carotid), blood glucose, and hepatic glycogen were measured. Within 30 minutes, histamine evoked a significant increase in blood glucose, and a decrease in hepatic glycogen, and a reduction in blood pressure. However, rats treated with the H-2 blocker metiamide or with a combination of H-1 and H-2 blockers did not show as significant a hypotensive response as rats treated with the H-1 blocker diphenhydramine alone. The hyperglycemic-glycogenolytic response to histamine was modified by diphenhydramine as well as by a combination of blockers, but not by metiamide alone. These results suggest that a) the hypotension did not initiate the hyperglycemic and glycogenolytic response; b) the H-2 blocker metiamide has little effect on the hyperglycemic response to exogenous histamine; and c) the H-1 blocker diphenhydramine may have antihyperglycemic properties.

Topics: Animals; Blood Glucose; Blood Pressure; Diphenhydramine; Drug Therapy, Combination; Histamine; Hyperglycemia; Isotonic Solutions; Liver Glycogen; Male; Metiamide; Rats; Rats, Inbred Strains; Ringer's Solution; Shock; Thiourea