Killing of arterial smooth muscle cells by chylomicron remnants

Chylomicron remnants were found to be cytotoxic to cultured arterial smooth muscle cells. Cell death was estimated by two methods: colourimetric assay using a tetrazolium salt and trypan blue staining. Both methods showed considerable cell death. Twenty-five micrograms of cholesterol/ml of chylomicron remnants appeared not to injure smooth muscle cells; however, greater concentrations (= and >50 mu g cholesterol/ml) caused considerable damage. Our observations may offer a possible cause of cell death in atherosclerotic plaques. (C) 1996 Academic Press, Inc.