Metoclopramide protection of diazinon-induced toxicosis in chickens.
The efficacy of metoclopramide for preventing organophosphate insecticide-induced (diazinon) toxicosis was evaluated in 7~14 days old chicks. Injection of metoclopramide at 25 mg/kg, s.c. 15 min before diazinon increased the oral 24 h median lethal dose of the insecticide in the chicks by 80%. Metoclopramide alone inhibited the in vitro and in vivo plasma and whole brain cholinesterase activities of the chicks. Metoclopramide pretreatment at 100 mg/kg, s.c. reduced the extent of cholinesterase inhibition that was caused by diazinon (10 mg/kg, p.o.) in the plasma and whole brain by 24% and 7%, respectively. Diazinon at 10 mg/kg, p.o. produced signs of cholinergic toxicosis in the chicks, and these signs included salivation, lacrimation, gasping and convulsions within 2 h, and the 2-h and 24-h lethalities were 88 and 100%, respectively. Metoclopramide at the dose rates of 12.5, 25, 50, 100 and 200 mg/kg, s.c. given 15 min before diazinon (10 mg/kg, p.o.) variably decreased the occurrence of toxic manifestations in the chicks. The highest dose of metoclopramide (200 mg/kg, s.c.) reduced the 2-h and 24-h lethality of diazinon to 75% each and it reduced the overall toxicity score of diazinon by 32%. The data suggest that metoclopramide pretreatment only partially protected chicks against the acute toxicity of diazinon.
Department of Physiology, Biochemistry and Pharmacology, College of Veterinary Medicine, University of Mosul, Mosul, Iraq.
M H
MH
Al-Zubaidy
F K
FK
Mohammad
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D002645:Chickens; D002800:Cholinesterase Inhibitors / Q000627:therapeutic use; D002802:Cholinesterases / Q000097:blood / Q000378:metabolism; D003976:Diazinon / Q000506:poisoning* / Q000633:toxicity; D004347:Drug Interactions; D005260:Female; D007306:Insecticides / Q000506:poisoning* / Q000633:toxicity; D007928:Lethal Dose 50; D008297:Male; D008787:Metoclopramide / Q000627:therapeutic use*; D011201:Poultry Diseases / Q000139:chemically induced / Q000188:drug therapy / Q000517:prevention & control*
D002800:Cholinesterase Inhibitors; D007306:Insecticides; D002802:Cholinesterases; D008787:Metoclopramide; D003976:Diazinon