Effects of dietary cyclopropene fatty acids on the mixed function oxidase system of the rainbow trout (Salmo gairdneri).

Dietary cyclopropene fatty acids (CPFA) in rainbow trout (Salmo gairdneri) decreased cytochrome P-450 and b5 content and NADPH-cytochrome c reductase activity 67.8 percent, 22.0 percent, and 38.4 percent respectively compared to control-fed trout after 22 days. Dietary CPFA induced benzo(alpha)pyrene aryl hydrocarbon hydroxylase 37.5 percent over controls for the same time period. Microsomal protein levels were consistently lower in CPFA-fed trout. This pattern remained established in CPFA-fed trout for the duration of the experiment (74 days). The data suggest a possible mechanism by which dietary CPFA act as co-carcinogens.