[Protective effects of apolipoprotein CII on endothelial cell injury induced by low density lipoprotein].

Human umbilical vein endothelial cells (EC) were cultured. The protective effects of high density lipoprotein (HDL) and apolipoprotein CII (apoCII) on the morphology and function of EC injured by low density lipoprotein (LDL) were studied by observing the morphological changes with phase-contrast and transmission electron microscopy, measuring the release of lactate dehydrogenase (LDH) and secretion of 6-Keto-prostaglandin F1 alpha. The EC injured by LDL showed cell contraction, membrane damage, increased release of LDH and decreased secretion of PGI2. When HDL or apoCII was added to culture media before LDL addition, the EC showed normal morphology, normal LDH release and PGI2 synthesis. The results indicated that both HDL and apoCII can resist the injurious effect of LDL on cultured EC and that apoCII as well as HDL may play an important role in combating atherogenesis.