Objective:To explore the relationship between the severity of cardiovascular disease with the expression of apolipoprotein(a) [apo(a)] and apolipoprotein B(apoB) in peripheral blood and their location in peripheral blood cells.Methods: In this report,we selected 4 patients with angiography which indicated that three coronary arteries were narrowed and 5 control patients with normal angiography.Arterial blood was collected and analyzed for lipid parameters in plasma.The mRNA expression of apo(a) and apoB in peripheral white blood cells and platelets were determined by RT-PCR and their protein expression by western blot.Moreover,the expression and location of apo(a) and apoB in white blood cells were determined by confocal microscopy and computer 3D analysis.Results: In plasma,levels of high density lipo-protein-cholesterol(HDL-C) and apolipoprotein A-Ⅰ(apoA-Ⅰ) in cardiovascular disease(CVD) patients were significantly less than those in the control patients[(0.62?0.05) mmol/L,(0.78?0.08) mmol/L vs(0.81?0.15) mmol/L,(0.9?0.07) mmol/L,P0.05).Studies with confocal microscopy indicated that proteins of apo(a) and apoB were co-expressed by a few cells of leukocytes and the ratio of apoB/apo(a) in cardiovascular disease patients was significantly less than that in the control patients(optical density value 1.60?0.12 vs 4.40?0.35,P