Denervation supersensitivity of striatal D2 dopamine receptors is restricted to the ventro- and dorsolateral regions of the striatum.

The precise topographical changes in striatal D2 dopamine receptors that occur after neurotoxic lesion of the mesostriatal dopaminergic pathway have been studied autoradiographically in the rat through the use of [3H]spiperone as a ligand. 6-Hydroxydopamine-induced lesion of the dopaminergic afferents to the striatum caused an increase in [3H]spiperone binding in the ventro- and dorsolateral but not in the ventro- and dorsomedian aspects of the striatum. This lesion caused a loss of tyrosine hydroxylase-like immunoreactivity in all striatal subregions. These results demonstrate that not all striatal D2 dopamine receptors are able to proliferate after dopaminergic denervation.