Effect of feeding different levels of mustard oil in monkeys.

Three groups, each of 9 adult male monkeys were maintained for about 18 months on diets containing mustard oil, either 5 or 10%; or 10% peanut oil, respectively. Histological examination of hearts of monkeys fed either 5 or 10% mustard oil diets did not reveal any abnormality attributable to mustard oil intake, such as vacuolation and fibrosis of myocardium. However, the oxygen consumption, RCR and ADP/O ratio, were significantly lower in the mitochondria isolated from monkeys receiving 10% mustard oil than those isolated from 10% peanut oil receiving monkeys, in the left ventricle but not in the right ventricle. Moreover, the oxygen consumption in the homogenates of left ventricles of monkeys receiving mustard oil, either 5 or 10%, was significantly lower as compared to that in 10% peanut oil controls. These data indicate that ingestion of mustard oil is associated with decreased oxidative capacity of heart mitochondria. They also suggest that the homogenates of the hearts of monkeys receiving mustard oil may contain a factor which further inhibits mitochondria oxidation.