Study of the early blood glucose response of mice to alloxan.

The initial hyperglycemia in alloxan-treated mice was decreased by adrenalectomy and hypophysectomy, and abolished by occlusion of the hepatic blood flow for 5 min. or treatment with insulin after alloxan injection. No effect on the initial hyperglycemic response to alloxan was found in mice pretreated with phentolamine, or in those given alloxan after sham operation or after removal of ligatures for temporary occlusion of hepatic artery and portal vein. The concentrations of serum insulin and liver glycogen were decreased one and four hours after alloxan injection. The initial hyperglycemia is believed to be due to inhibition of insulin secretion by the B-cells and to the mobilization of glycogen from the liver. Pituitary and adrenocortical activity may contribute to this hyperglycemia. The origin of the hypoglycemic phase does not seem to be pancreatic, but may be hepatic.