Similar behaviour of lecithin:cholesterol acyltransferase and pseudocholinesterase in liver disease and hyperlipoproteinemia.

Using exogenous substrate for its assay, lecithin:cholesterol acyltransferase (LCAT) was found to be decreased in liver disease and higher than normal in endogenous hypertriglyceridemia. LCAT activity was positively correlated with serum cholesterol and triglyceride. However in the six patients with excessive hypertriglyceridemia (type V), LCAT activity was lower than in type IV hyperlipoproteinemia. LCAT activity was not changed significantly in type II-a hyperlipoproteinemia. A striking parallel was noted between plasma LCAT and serum pseudocholinesterase activity. It suggested that both these liver secretion enzymes might be induced by an accelerated turnover of serum lipids and lipoproteins. Pathogenical implications of these findings are briefly discussed.