Little is known about the pathophysiological mechanisms responsible for the higher incidence of atherosclerosis in hypertensive subjects. In view of the known atherogenic role of low-density lipoproteins (LDL), the aim of the present study was to evaluate possible differences in LDL binding to cultured aortic smooth muscle cells from normotensive and hypertensive rats. We studied the time-dependence and dose-dependence of LDL binding to both cell types. Low density lipoprotein binding to smooth muscle cells from the hypertensive rat was significantly higher than that to smooth muscle cells from the normotensive rat. This mechanism might explain the higher incidence of atherosclerotic lesions observed in hypertension.