Central action of drugs acting on the cholinergic muscarinic receptor I. Influence of cholinomimetic drugs administered into the lateral cerebral ventricle on behavior in rats.

Carbachol (CCh), physostigmine (Pht) and pilocarpine (Pil) injected into the lateral cerebral ventricle (ivtr), diminished spontaneous motility and open-field performance, lowered body temperature, depressed amphetamine-induced hypermotility, and inhibited amphetamine stereotypy. On the other hand, they had no effect on duration of hexobarbital anesthesia, except Pil, which slightly prolonged it, or on the action of threshold dose of pentetrazole and maximal electroshock. The compounds raised levels of "free" and "total" ACh, but not those of "bound" ACh. Level of NA in the brain was decreased, while level of DA was unaltered. These results are further evidence of an inhibitory influence of cholinomimetic drugs on behavior in animals.