The cholinergic influences on aggression in isolated mice.

The influence of cholinomimetics and cholinolytics on the isolation-induced aggression in mice was examined. Arecoline, bethanechol, carbachol, oxotremorine, pilocarpine, and physostigmine were found to potentiate aggression, while cholinolytics - atropine and scopolamine - suppressed aggressive behavior. Cholinolytics with no central action did not inhibit aggression. The results indicate that in addition to catecholamines also the cholinergic system may participate in the behavioral model under examination.