Angiotoxic effects of dietary 7-ketocholesterol in chick aorta.

Although dietary 1-ketocholesterol treatment had little effect on plasma and liver lipid metabolism, aortas from chickens treated with 7-ketocholesterol contained numerous dead and dying smooth muscle cells. Chicks receiving dietary cholesterol, in amounts equal to or greater than the amount of 7-ketocholesterol, did not demonstrate significant smooth muscle cell degeneration. After eight weeks, a combined diet of 1% cholesterol plus 10-20 mg/day 1-ketocholesterol produced no larger amounts of aortic lipid deposition, and no greater increases in smooth muscle cell degeneration than a comparable group receiving 7-ketocholesterol alone. The abdominal aorta was always more severely damaged than the ascending arch or thoracic aorta in chicks fed 7-ketocholesterol. The results demonstrate a potent angiotoxic effect of 7-ketocholesterol.