Epinephrine-insulin antagonism on free fatty acid release

¹ Department of Physiology, Hahnemann Medical College and Hospital of Philadelphia, Philadelphia, Pennsylvania

The effects of epinephrine or norepinephrine were studied in dogs receiving insulin plus glucose prior to and during administration of the amine. Epinephrine caused a significantly smaller elevation of free fatty acids (FFA) with than without insulin plus glucose administration. Blood sugar responses were quantitatively similar. Epinephrine increased both hepatic uptake of FFA and hepatic release of glucose; these changes were similar to the ones found previously in dogs not receiving insulin plus glucose. The action of norepinephrine on elevating plasma FFA was only slightly and not significantly affected by the administration of insulin plus glucose. When the order of drug administration was reversed, infusion of insulin plus glucose lowered plasma FFA levels and hepatic FFA uptake in animals already receiving either epinephrine or nonepinephrine.