Chloroform induction of ornithine decarboxylase antizyme (ODC-AZ) in male rat liver.
Savage-RE Jr.; Pereira-MA; DeAngelo-AB
J Toxicol Environ Health 1988 Sep; 25(1):97-101
The induction of ornithine-decarboxylase antizyme by chloroform (67663) stimulation was assessed in male and female Charles River CDF Fischer-344-rats. The animals were given chloroform at a dose of 3 millimoles per kilogram body weight by daily intraperitoneal injection for a period of 1, 3, or 7 days. Ornithine-decarboxylase antizyme activity was determined following the exposure period by inhibition of ornithine-decarboxylase activity in an hepatic microsomal preparation. Chloroform stimulation of ornithine- decarboxylase activity was greatest at 18 hours after a single treatment, and repeated dosing progressively reduced the response of the liver microsomal enzyme. DEAE-cellulose chromatography showed increased ornithine-decarboxylase antizyme activity in liver microsomal fractions from treated male animals only. The antizyme activity was recoverable from the chloroform treated male rats and positive treated controls by Sephadex-G75 molecular sieving. The authors conclude that the inhibition of microsomal ornithine- decarboxylase after repeated chloroform stimulation is due in part to ornithine-decarboxylase antizyme activity in male, but not in female, rats.
NIOSH-Author; Chlorinated-hydrocarbons; Carcinogenesis; Laboratory-animals; Enzymatic-effects; Hepatotoxicity; Enzyme-activity; Sex-factors; Liver-microsomal-enzymes
Journal of Toxicology and Environmental Health