Effect of the fungicide benomyl on xenobiotic metabolism in rats.
The effect of benomyl administered orally (p.o.) and intraperitoneally (i.p.) on the activity of hepatic microsomal mixed-function oxidases (MFOs) was studied in rats. A dose of 100 mg/kg given i.p. reduced the activities of several hepatic drug-metabolizing enzymes 24 h following the treatment. A similar reduction in the activities of the MFOs was also noted 24 h following oral benomyl administration at a dose of 500 mg/kg. Furthermore, in vivo inhibition of drug metabolism by benomyl was demonstrated by increased pentobarbital sleeping-time 24 h after p.o. as well as i.p. dosing. No alterations were found in the serum sorbitol dehydrogenase (SDH) at 24 h after i.p. or oral benomyl indicating a lack of hepatotoxic effect. These results indicate that benomyl shows a route-independent effect on MFOs and is not toxic to the liver.
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Department of Physiology, Pharmacology and Toxicology, School of Veterinary Medicine, Tuskegee University, AL 36088.
D000284:Administration, Oral; D000818:Animals; D001542:Benomyl / Q000008:administration & dosage / Q000633:toxicity*; D007274:Injections, Intraperitoneal; D007064:L-Iditol 2-Dehydrogenase / Q000097:blood / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects* / Q000201:enzymology; D006899:Mixed Function Oxygenases / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D012890:Sleep / Q000187:drug effects
D006899:Mixed Function Oxygenases; D007064:L-Iditol 2-Dehydrogenase; D001542:Benomyl