Brain monoamine oxidase in suckling rabbits treated with organophosphorus compound. I. Acute intoxication.

In 16-day-old rabbits treated with dichlorvos 8 mg/kg per os the activity of monoamine oxidase A form (MAO A) in brain was studied. A short-lasting decrease of brain MAO A was followed by a recovery of enzyme activity within 120 min. In parallel to changes in MAO A activity breathing disturbances were observed. It is concluded that the decrease of MAO A was due rather to hypoxia than to a direct effect of dichlorvos. In 16-day-old rabbits clorgyline (2 mg/kg) and tranylcypromine (10 mg/kg) were potent inhibitors of MAO A but deprenyl and pargyline were ineffective.