Effect of Pravastatin sodium, a new inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, on very-low-density lipoprotein composition and kinetics in hyperlipidemia associated with experimental nephrosis

Abstract

The effect of Pravastatin sodium (CS-514), a new inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA R) on very-low-density lipoprotein (VLDL) composition and kinetics was studied in normal and experimental nephrotic rats under fasting conditions. Nephrotic rats, induced by a single intraperitoneal injection of puromycin aminonucleoside (100 mg/kg body weight), had significantly higher plasma lipids and apoprotein (apo) B concentrations than controls. The hypertriglyceridemia associated with nephrosis was mainly due to a markedly elevated VLDL-triglyceride (TG) concentration. Pravastatin sodium was administrated as a 0.04% solution in drinking water for 7 days to normal control and nephrotic rats. Plasma TG concentration in both control and nephrotic rats was significantly reduced by the treatment with Pravastatin, but plasma cholesterol levels were not reduced by the treatment in either group of rats. TG, cholesterol, phospholipid, and apo B concentrations in nephrotic VLDL were significantly reduced by Pravastatin treatment, whereas only TG was decreased in control VLDL. Pravastatin reduced the apo B 100+95 48 ratio in nephrotic VLDL. Pravastatin did not alter the lipid concentration of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) in control and nephrotic rats. VLDL-TG turnover studies showed that TG secretion rate was significantly suppressed by Pravastatin administration without affecting its removal in both groups of rats. These results suggested that Pravastatin, an inhibitor of cholesterol biosynthesis, can reduce VLDL concentration by rectifying the overproduction of VLDL exhibited in nephrotic rats.