Turning behavior after unilateral lesion of the subthalamic nucleus in the rat.

Unilateral stereotaxic lesions of the subthalamic nucleus of rats with kainic acid induced a transient spontaneous ipsiversive turning which was present for several days, and which could be blocked by i.p. administration of haloperidol. After the 20th postoperative day, when no spontaneous turning activity was present, i.p. administration of apomorphine or amphetamine in the kainic acid lesioned rats induced ipsiversive turning, while i.p. haloperidol in the same rats induced contraversive turning. These findings suggest that the subthalamic nucleus is involved in the dopaminergic mechanisms mediating turning behavior of rats.