title: Influence of nicotinic acid on metabolism of cholesterol and triglycerides in man.
abstract: The mechanisms for the hypolipidemic action of nicotinic acid were examined in 12 patients with hyperlipidemia. Most patients were studied in the hospital on a metabolic ward. The first month was a control period followed by 1 month on nicotinic acid. During treatment with nicotinic acid, the triglycerides (TG) decreased in total plasma by an average of 52% and in very low density lipoproteins (VLDL) by 36%. Transport rates of VLDL-TG were determined by multicompartmental analysis following injection of [3H]glycerol as a precursor. Nicotinic acid decreased transport (synthesis) of VLDL-TG by an average of 21%. Kinetic modeling of the VLDL-TG data suggested that the TG reduction was due to a decrease in TG content of VLDL and hence a reduction in lipoprotein size more than number. For the whole group, plasma cholesterol fell during nicotinic acid therapy by a mean of 22%. The drug produced no detectable changes in fecal excretions of cholesterol (neutral steroids) or bile acids. However, it induced a small but significant increment in hepatic secretion of biliary cholesterol that might have led to a net loss of cholesterol from the body even though this loss could not be detected by sterol balance. Despite this increase in outputs of biliary cholesterol, there was not a significant increase in molar % cholesterol or in % saturation of gallbladder bile. Therefore, it is doubtful that nicotinic acid enhances the risk for cholesterol gallstones.
mesh_terms: D000042:Absorption; D000328:Adult; D001646:Bile / Q000032:analysis; D002784:Cholesterol / Q000032:analysis / Q000097:blood*; D005243:Feces / Q000032:analysis; D006801:Humans; D006949:Hyperlipidemias / Q000188:drug therapy*; D008055:Lipids / Q000032:analysis; D008079:Lipoproteins, VLDL / Q000097:blood; D008297:Male; D008875:Middle Aged; D009539:Nicotinic Acids / Q000627:therapeutic use*; D014280:Triglycerides / Q000097:blood*
chemical_list: D008055:Lipids; D008079:Lipoproteins, VLDL; D009539:Nicotinic Acids; D014280:Triglycerides; D002784:Cholesterol