Carotid Artery Occlusion in Rats With and Without Arteriosclerosis

During the past several years we have investigated the pathogenesis of arteriosclerosis in repeatedly bred male and female rats. 1-4 The arterial lesions appear in the abdominal aorta first and progress throughout the other segments of the aorta.l In time, the coronary3 and eventually the carotid? arteries also show evidence of arterial degeneration. The carotid arteries manifest a particular predilection toward the development of mesenchymal or smooth muscle cell proliferation, intimal accumulation of mucopolysaccharide, medial elastolytic changes and, in advanced cases of arteriosclerosis, cartilaginous metaplasia and even bone formation. There is a sharp sex dichotomy in the development and consequences of arterial disease in that male breeder rats display minimal arteriosclerosis of the aorta but succumb in great numbers, often because of myocardial infarction. The female breeder survives for a much longer period despite the development of advanced arteriosclerosis with especially severe cartilaginous lesions in the carotid arteries which become markedly ectatic and tortuous. Because of our interest in experimental aspects of cerebrovascular disease,