[Effects of one-day food restriction on the metabolism and toxicity of organic solvents in rats].

Studies were made with male Wistar rats on the effects of 50% food restriction on the metabolism of eight organic solvents (chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,1-dichloroethylene, trichloroethylene, benzene, toluene and styrene) and on the hepatotoxicity induced by carbon tetrachloride inhalation at 400 ppm for 4 h. The activities of liver drug-metabolizing enzymes for these solvents were enhanced almost equally without exception by one-day food restriction, although the restriction produced no significant increase in the microsomal protein and cytochrome P-450 contents. Carbon tetrachloride hepatotoxicity was enhanced by the food restriction, as evidenced by a marked increase of serum glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) activities in the food-restricted rats. Histological findings of the liver also supported this finding. Thus, food restriction enhances metabolism of organic solvents in the liver, and can modify toxicity of some chemicals such as carbon tetrachloride, which need metabolic activation to become cytotoxic.