Increased hepatitic cholesterol production due to liver hypertrophy in rat experimental nephrosis

Control and nephrotic rats were compared as to the liver contents of cholesterol, phospholipid and the activity of microsomal 3-hydroxy-3-methylglutaryl-coenzyme A reductase. Whole liver homogenates as well as endoplasmic reticulum membrane samples showed increased free cholesterol and phospholipid mass in the nephrotics. Correction of the values by the protein content indicated membrane expansion, i.e. liver hypertrophy. However, total hepatic cholesterol synthesis as measured by the reductase activity was increased in the nephrotic rat. These results are in accordance with previous studies showing enhanced cholesterol production in experimental nephrosis. In short, enhanced cholesterol mass in the liver coexists with increased hepatic synthesis in the experimental model used.