Effect of estrogen on atherosclerotic lesions in various arterial segments of cholesterol-fed chicks.

Until recently it was believed that atherosclerotic lesions of the aorta induced by hypercholesterolemia always faithfully reflected changes in other arteries. Thus intensive experimental analysis of factors reducing hypercholesterolemia and protecting the aorta against atherosclerosis were undertaken in the belief that such factors would also protect the coronary and other arteries against atherosclerotic lesions. However, it is now knowniM that after administration of estrogen coronary arteries differ in their behavior from that of aorta. While con siderable attention has been directed to atherosclerotic lesions of coronary arteries in experimental animals, cerebral arteries have received little at tention, in spite of the frequent incidence of cerebral vascular disease in man. In the present study on chicks I have examined the effect of cho lesterol feeding and hypercholesterolemia on the tendency to lipids infil tration and atherosclerotic changes in arteries of the brain, heart, kidney, lung, liver and spleen as well as of aorta. The effect of estrogen adminis tration on these vessels was also studied.