Glucagon secretion in primary endogenous hypertriglyceridemia before and after clofibrate treatment

Abstract

Arginine-induced insulin and glucagon secretion preceding and following clofibrate treatment was studied in 13 patients with endogenous hypertriglyceridemia. A positive correlation was demonstrated between fasting insulin and triglyceride levels and between the fasting insulin/glucagon molar ratio and triglyceride levels. In patients with endogenous hypertriglyceridemia, arginine infusion induces a significantly increased glucagon response with respect to that found in controls. No correlation was found to exist between glucagon and free fatty acids (FFA) or between glucagon and triglyceride levels. The same lack of correlation was found in normal subjects rendered hypertriglyceridemic by means of Intralipid infusion, which did not modify the fasting glucagon-like immunoreactivity (GLI) or the GLI response to arginine. Clofibrate treatment induces a triglyceride reduction (ΔTG) which is correlated with the reduction in the insulin/glucagon molar ratio ( ΔI G ). After clofibrate treatment there is also a significant reduction in fasting GLI levels and in the insulin response to arginine, and an increase in the glucagon response. Clofibrate could exercise its hypolipidemic effect by modifying the relationship between insulin and glucagon levels.