Effect of patulin on hepatic monooxygenase in male mice.

The in vivo effects of patulin on hepatic monooxygenase enzymes in male mice were examined after single and multiple exposures (i.p.) to the mycotoxin. The animals were exposed to a single dose of 1, 3 or 4.5 mg patulin/kg or daily doses of 1.0 mg/kg for 5 or 14 days. After single exposure no significant effect was observed on hexobarbital hydroxylation while aniline hydroxylase increased significantly at 3 mg/kg and at 48 hr. The demethylation of aminopyrine and ethylmorphine increased significantly 48 and 72 hr after 3.0 or 4.5 mg patulin/kg doses. A 12% increase was observed in cytochrome P-450 content 48 hr after exposure to 1 or 3 mg/kg. NADPH-cytochrome C reductase was enhanced significantly at all 3 dose levels at 48 hr. At 24 hr hepatic NADPH-dependent dehydrogenase activity increased 38 and 46% in animals exposed to a single dose of 3 mg patulin/kg, respectively. No effect of patulin was observed on the hepatic drug metabolizing enzymes examined except hexobarbital oxidation in mice exposed to multiple doses of patulin. Patulin at best was a weak inducer of the hepatic mixed function oxidase system.