[Effect of polyunsaturated phosphatidylcholine on the activity of antioxidant and lipolytic enzymes in alimentary hypercholesterolemia in irradiated rats].

A high-cholesterol diet containing 3.5% cholesterol, 0.2% methyl thiouracil and 20% of heated sunflower-seed oil caused an increase in the content of cholesterol, triacylglycerols, diene conjugates and in the activity of phospholipase A2 in rat liver and of serum total cholesterol and cholesterol of low density lipoproteins, and a decrease in the activity of hepatic cholesterol esterase, in the fractional activity of lecithin:cholesterol acetyl transferase (LCAT), in the activity of the enzymes involved in the lipolytic transformation of lipoproteins and in the serum levels of very low density lipoprotein cholesterol. The content of malonic dialdehyde in liver tissue and molar activity of LCAT in blood serum were increased after preirradiation (0.5 and 5.0 Gy) of rats kept on the cholesterol diet. The preparation of polyunsaturated phosphatidylcholine was shown to decrease the content of triacylglycerols and diene conjugates in liver tissue of rats with alimentary hypercholesterolemia. In rats irradiated in a dose of 0.5 Gy the phosphatidylcholine preparation decreased the content of cholesterol in liver tissue and blood serum, exhibited the normalizing effect on the content of cholesterol of high density lipoproteins, on the activity of superoxide dismutase and glutathione peroxidase; in a dose of 5.0 Gy this phosphatidylcholine preparation normalized the content of malonic dialdehyde, activity of the enzymes involved in lipolytic transformation of lipoproteins and increased the LCAT activity.