Effect of forebrain commissurotomy on recovery from unilateral 6-OHDA lesions of the substantia nigra and circling induced by apomorphine.

We studied the influence of transection of the interhemispheric fiber systems between the anterior and posterior commissures on recovery from turning behavior induced by a unilateral substantia nigra lesion in rats. It has been argued that the crossed nigrostriatal projection is involved in this recovery, and its site of crossing has been suggested to lie within the region split. Animals which received this transection did not differ from controls with respect to time-course and extent of recovery from lesion-induced asymmetries within the 7 postlesion days examined. Additionally, the commissurotomy did not prevent apomorphine-induced contraversive circling.