Effects of dietary saturated and polyunsaturated fat on lipoprotein lipase and hepatic triglyceride lipase activity

The effects of saturated and polyunsaturated dietary fat on the lipolytic activity of post-heparin plasma, lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) were studied in the rat. The lipolytic activity was studied from 0 to 60 min using labelled chylomicrons as the substrate. Triacylglycerol hydrolysis rate was higher for the plasma of rats fed high fat diets (14% fat by weight). Chylomicrons of rats fed saturated or unsaturated fats were hydrolyzed at the same rate within the first 15 min but afterwards hydrolysis of chylomicrons of rats fed saturated fat was slower. The activities of LPL and HTGL were increased by high fat diets. Unsaturated fat increased more LPL activity than saturated fat conversely, HTGL activity was enhanced more by saturated fat than by unsaturated fat.