Protection by a small dose of carbon tetrachloride against the toxic effects of dimethylnitrosamine in rats.

  • 1 April 1974
    • journal article
    • Vol. 55  (2) , 203-12
Abstract
A single intragastric dose of carbon tetrachloride (CCl4) (0·01-2·5 ml/kg) protected male Sprague-Dawley rats against the toxic effects of dimethylnitrosamine (DMN). This appeared to be due to the reduction in the levels of DMN-demethylase, a microsomal enzyme involved in the metabolism of DMN. The increase in the LD50 of DMN and the reduction in demethylase levels were observed within 20 minutes of dosing with CCl4. The changes were maximal by 12 hours, persisted until 48 hours and began to recover between 48 and 60 hours. The LD50 of DMN and the level of DMN-demethylase returned to normal between 120 and 144 hours.