Effect of antidiabetic agents on the increase in glycemia and insulinemia caused by refeeding in hereditarily diabetic rats.

The hypoglycemic agents, glibenclamide and repaglinide, when administered intragastrically to overnight fasted hereditarily diabetic animals, were found to oppose the rise in the plasma insulin/glucose ratio otherwise evoked by refeeding of the GK rats. Such was not the case after oral administration of glimepiride, despite the fact that this sulfonylurea minimized the rise in glycemia associated with refeeding. The altered restoration of a high insulin/glucose ratio in GK rats that received glibenclamide or repaglinide before refeeding suggests that these long-acting hypoglycemic agents may delay the refeeding-induced relief of the B-cell from the fasting-associated refractoriness to glucose.