[The sensory and motor components of different forms of learned movement during a change in the activity of the neostriatal cholinergic system].

The role of the neostriatal cholinergic system in the regulation of sensory controlled movements were studied using two behavioral models: 1) maintenance acquired extension of forelimb during proper time (rats) and 2) prolonged conditional flexion of hindlimb (dogs). It was found that injections of carbacholine (Car, 0.03 mkg) into the dorsolateral part of nucleus caudatus (NCd) of rats did not considerable change the movement connected with maintenance of forelimb tonus, while injections of Car (0.05-0.1 mkg) into the same area of the NCd of dogs were accompanied by improved performance of movement connected with maintenance of hindlimb tonus. It is possible to suggest the follows: 1. The neostriatal mechanisms of regulation of fore- and hindlimb tonus maintenance are different. 2. The neostriatal mediator of mechanisms of tonus regulation and regulation of somesthetic control of maintenance of this tonus are probably different too. Bilateral Car microinjections (0.03 mkg) into NCd of rats improved the discriminative active avoidance learning in T-maze. The discrimination of sound signals in dogs were also significantly improved after Car injections (0.05-0.1 mkg) into the NCd. Thus, data obtained at the different behavioral models and different animals suggest that cholinergic system of Neostriatum takes part in the regulation of both motor and sensory components of learned movements realization. The possible mechanisms of this regulation are discussed.