Abstract
1. The influence of microsomal enzyme inducers and inhibitors on the metabolism of [U-14C]benzene in the rat was examined.
2. Pre-treatment of animals with the inhibitors piperonyl butoxide and cobaltous chloride tended to reduce the urinary excretion of metabolites in 24 h but increase the overall urinary excretion. Piperonyl butoxide tended to increase expired benzene.
3. Pre-treatment of animals with the inducer phenobarbital tended to increase urinary excretion of metabolites but decrease expired benzene, as did pretreatment with benzene itself.
4. All pre-treatments appeared to increase the excretion of phenolic glucu-ronides, particularly benzene pre-treatment. Phenobarbital and benzene pre-treatment tended to increase phenylmercapturic acid excretion and benzene pre-treatment markedly increased excretion of quinol.
5. The results are discussed in relation to the effect of microsomal enzyme inhibitors and inducers on benzene-induced bone marrow toxicity.