Effect of yohimbine on amitraz-induced CNS depression and bradycardia in dogs.
Yohimbine was studied to examine its effectiveness in preventing central nervous system(CNS) depression and bradycardia induced by amitraz (N'-(2,4-dimethylphenyl)-N-[(2,4-dimethylphenyl-imino)-methyl]-N-methyl- methanimide). In control open-field activity experiments, the dogs showed high numbers of grid-line crossings in the first 5 min (exploratory phase), and subsequently low numbers of grid-line crossings (nonexploratory phase). An iv injection of amitraz (1 mg/kg) abolished both the exploratory and nonexploratory phases and caused bradycardia. Yohimbine alone caused a trend to increase the open-field activity in the nonexploratory phase. In addition, yohimbine prevented the bradycardia and suppression of open-field activity induced by amitraz. The results suggest that yohimbine has a potential to be used as an antidote for amitraz overdose.
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D000818:Animals; D002492:Central Nervous System Depressants / Q000037:antagonists & inhibitors*; D004285:Dogs; D005106:Exploratory Behavior / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects*; D007306:Insecticides / Q000037:antagonists & inhibitors*; D009043:Motor Activity / Q000187:drug effects; D014052:Toluidines; D015016:Yohimbine / Q000494:pharmacology*
D002492:Central Nervous System Depressants; D007306:Insecticides; D014052:Toluidines; D015016:Yohimbine; C014983:amitraz