Influence of short-term administration of clofibrate on insulin and glucagon response to protein ingestion in man.

Nine normal and two mildly hypertriglyceridemic subjects were treated with 2 g of clofibrate per day for 8 days. A significant fall in serum triglyceride and cholesterol concentration was observed from the second day onwards whereas free fatty acid levels were minimally affected. Insulin and glucagon responses to the ingestion of 200 g of meat were tested before and at the end of clofibrate treatment. Insulin response was significantly depressed (-28 +/- 12%) by the drug whereas glucagon response was enhanced but not to a significant degree. The ratio between insulin response and glucagon response was decreased by 38 +/- 11% (p less than 0.01) after treatment. A positive correlation was observed between the effects of clofibrate on basal triglyceride concentration on one hand and the effects of the drug on insulin and insulin/glucagon response to the protein meal on the other hand. Since insulin and glucagon are known to influence triglyceride metabolism, our data are compatible with the concept that the hypotriglyceridemic effect of clofibrate is--at least partly--related to the observed changes in insulin and glucagon reactivity.