Autoradiographic localization of D 1 and D 2 dopamine receptors in the human brain

The distribution of dopamine D 1 and D 2 receptors in several human brain regions was investigated using autoradiography with the radioligands [3H]SCH 23390 and [3H]spiroperidol. The highest densities of both dopamine receptor types are seen in the nucleus caudatus, putamen and nucleus accumbens. Wheras the density of the D 2 receptors is similar in the two segments of the globus pallidus, the pars medialis of the globus pallidus contains three-fold higher concentration of D receptors than the pars lateralis. D 1 and D 2 receptors are present in the amygdala and substantia nigra. Both receptor types are absent in the cerebellum. The thalmus contains low densities of D 1 receptors but no D 2 receptors. Only D 2 receptors are seen in the anterior lobe of the pituitary gland. The whole cerebral cortex is rich in D 1 receptors, while D 2 receptors in low concentrations are confined to the entorhinal area and cingulate cortex