Investigation of the Mechanism of Action of Nicotinic Acid on Serum Lipid Levels in Man

Abstract

Nicotinic acid was found to lower serum lipid concentrations, thereby confirming reports from other laboratories. The mechanism of action of nicotinic acid does not appear to be related to depletion of methyl groups in the body because administration of methionine had no influence on the action of nicotinic acid in lowering serum lipid levels. Nicotinic acid was shown to have no influence on the fecal excretion of bile acids and sterols. Other possible mechanisms of action are discussed. Evidence is presented which gives strong support to the thesis that nicotinuric acid, a metabolite of nicotinic acid, is responsible for the hypolipemic effect of nicotinic acid.