Effects of Combination of PCB and DDT on Vitamin A Storage and Lipid Peroxide Formation in the Liver of Rats
1985 Volume 38 Issue 4 Pages 265-272
Details
1985 Volume 38 Issue 4 Pages 265-272
The experiments were performed to clarify the effects of combination of polychlorinated biphenyls (PCB) and p, p′-dichlorodiphenyltrichloroethane (DDT) on the hepatic vitamin A storage, lipid peroxide formation and cytochrome P-450 induction. Weanling male rats of the Sprague-Dawley strain aged 3 weeks were used in this study.
1. When the animals fed on the diet containing 0.01% or 0.025% level of PCB for 10 days, an enlargement of liver, marked reduction of vitamin A storage, increase of lipid peroxide formation and induction of cytochrome P-450 in the liver were observed. The growth of rats on 0.025% PCB was not significantly different from the control.
2. When the rats fed on the diets containing DDT at various levels from 0 to 0.03%, no growth retardation was observed at all. At the levels of DDT over 0.02%, vitamin A content in the liver was significantly decreased.
3. When the diets contained 0.025% PCB and 0.01% DDT, there was no suppression of the animal growth as compared with that on PCB alone, but further enlargement of the liver was noted in the combination of these compounds.
4. The combination of PCB and DDT did not have an effect of significant reduction in the hepotic and serum vitamin A content as compared with the result of single PCB administration.
5. An increase in peroxide formation in the liver was less in the rats fed on the combination of both compounds than those fed either on PCB or DDT alone.
6. Cytochrome P-450 in hepatic microsome was also increased by either single or combined administration. The combination effect was not additive.
7. The hepatomegaly, the reduced vitamin A storage, and the increased content of cytochrome P-450 induced by the combined PCB and DDT dose were not completely prevented by an excess administration of either methionine, vitamin E or both. Vitamin E administration restored the hepatic lipid peroxide content to normal, whereas methionine showed no effect.
