[Nigrostiatally induced motor reactions in the rat. II. Cholinergic effect on rotational behavior and posture...

The rotational behaviour released in rats by apomorphine (5 mg/kg i.p.) following nigrostriatal lesions with 6-hydroxydopamine can be inhibited both by oxotremorin (1 mg/kg i.p.) and by injections of carbachol (30 mug) in the Nucleus caudatoputamen or Substantia nigra of the intact side. The rotations released in healthy animals by intrastriatal injections of apomorphine or carbachol are in opposite directions. The bendings of the body towards the side of injection (posture asymmetry) also observed after apomorphine administration in the Substantia nigra are inhibited by intrastriatal injections of carbachol. The results indicate that a dopaminergic-cholinergic interplay in the Nucleus caudatus, corresponding to the control functions of this nuclear area, is involved in the animals movement and poise.