Comparative toxicological studies of chlorpyrifos in rats and chickens.
Rats and chickens were given single oral doses of 50 mg chlorpyrifos/kg to compare toxic effects in these 2 species. Oral administration resulted in decreased cytochrome P-450 and aminopyrine N-demethylase activities and increased cytosolic glutathione S-transferase activity in rats. On the contrary, there was increased cytochrome P-450 and aminopyrine N-demethylase activities in chickens. A significantly higher inhibition of serum cholinesterase (82%) was noted in rats than in chickens (55%). Serum gamma-glutamyl transferase, a marker of hepatotoxicity, remained unchanged in both species, indicating the absence of hepatotoxicity. These studies project chlorpyrifos to be an inhibitor of hepatic microsomal drug-metabolizing enzymes in rats and an inducer in chickens, and a non-hepatotoxic organophosphate insecticide in both species when given at the dosage of 50 mg/kg.
Vodela
J K
JK
Department of Physiology and Pharmacology, School of Veterinary Medicine, Tuskegee University, AL 36088, USA.
Dalvi
R R
RR
D000284:Administration, Oral; D000818:Animals; D002645:Chickens; D004390:Chlorpyrifos / Q000008:administration & dosage / Q000633:toxicity*; D002802:Cholinesterases / Q000097:blood / Q000187:drug effects; D003577:Cytochrome P-450 Enzyme System / Q000187:drug effects; D005982:Glutathione Transferase / Q000187:drug effects; D008099:Liver / Q000187:drug effects* / Q000201:enzymology* / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology; D010088:Oxidoreductases / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley
D003577:Cytochrome P-450 Enzyme System; D010088:Oxidoreductases; D005982:Glutathione Transferase; D002802:Cholinesterases; D004390:Chlorpyrifos