Spontaneous and drug-induced rotation following localized 6-hydroxydopamine and kainic acid-induced lesions of the neostriatum.

Twelve groups of rats received small localized lesions produced by either 6-hydroxydopamine (6-OHDA) or kainic acid (KA) in one of six placements in the right neostriatum. All groups lesioned with 6-OHDA showed ipsilateral spontaneous and amphetamine-induced rotation and contralateral apomorphine-induced rotation. All groups lesioned with kainic acid showed ipsilateral spontaneous rotation on day 1 following the lesion but contralateral rotation by day 8, and no significant rotation to injections of either amphetamine or apomorphine. The histology suggested that the lesions were topographically specific, and it is therefore concluded that the neostriatum is topographically homogeneous in the mediation of rotational behaviour as measured in automated rotometers.