Effect of 20-methylcholanthrene on the development of atherosclerosis in LAP quails

We studied the effect of 20-methylcholanthrene, a carcinogen, on atherosclerosis in the ascending aorta and brachiocephalic arteries of hyperlipidemic and atherosclerosis-prone (LAP) quail. A total of 66 quails were divided into 6 groups and fed the following diets: Group I, basal; Group II, basal+low dose of carcinogen; Group III, basal + high dose of carcinogen; Group IV, basal + 0.2% cholesterol; Group V, basal + 0.2% cholesterol + low dose of carcinogen; and Group VI, basal + 0.2% of cholesterol + high dose of carcinogen. The carcinogen was dissolved in corn oil at 2 mg/ml and 4 mg/ml as low and high doses respectively, and was given orally twice weekly. Marked elevation of the serum cholesterol level and significant lipid-rich aortic lesions were observed in all the cholesterol-fed groups after 12 weeks. Although the serum cholesterol level in Group VI was lower than that in Group IV, the severity of the atherosclerotic lesion was greater in the former than in the latter. An immunohistochemical study showed a positive reaction of DBA, PHA and OKM-1 with the lipid-containing cells of aortic intimal lesions.