The effects of muscarinic cholinergic blockade upon shock-elicited aggression

Graded dosages of atropine sulfate, atropine methyl nitrate, scopolamine hydrochloride, and scopolamine methyl nitrate were administered to rats and shock-elicited fighting frequencies determined. Central cholinergic blockade decreased fighting at appropriate dosages, but peripheral cholinergic blockade had little or no effect upon shock-elicited aggression. These result suggest that shock-elicited aggression is similar to other kinds of agonistic behavior (e.g., isolation-induced fighting and muricide) in that a central cholinergic system is apparently involved in its mediation.