Central administration of alloxan impairs glucose tolerance in rats.

By means of oral glucose tolerance test (OGTT), we investigated glucose tolerance in rats pre-treated with intracerebroventricular and subcutaneous non-diabetogenic dose of betacytotoxic drug alloxan 7 days before OGTT. Being normoglycemic and normoinsulinemic pre-OGTT, at 30 minutes post-OGTT, alloxan intracerebroventricularly-treated rats had a lower glucose and a higher insulin plasma levels in comparison with controls or alloxan subcutaneously treated animals. Centrally administered alloxan seems to have brain related effect on the regulation of peripheral glucose tolerance and insulin secretion.