Heterogeneous distribution of dopamine D1 and D2 receptors in the human ventral striatum.

The distribution of dopamine D1 and D2 receptors was examined in the human ventral striatum using in vitro quantitative autoradiography. Both D1 and D2 receptors have a markedly heterogeneous distribution, that includes regional differences in binding for the D1 receptor and a pattern of smaller heterogeneities for both receptors. The latter heterogeneities in D1 and D2 binding are interrelated and, in addition, appear to be related to inhomogeneities in the acetylcholinesterase histochemistry and cellular density of the ventral striatum. The present data indicate that in the human ventral striatum the ratio between D1 and D2 receptors varies widely from one area to another.