ORIGINAL ARTICLES Effects of Cocaine on Dopamine Receptor Gene Expression: A Study in the Postmortem

The effects of chronic cocaine exposure on dopamine DI and D2 receptor gene expression in the human brain were studied in postmortem samples from chronic cocaine abusing and matched control subjects. U~ing in situ hybridization and receptor autoradiography toexamine messe ger ribonucleic acid (RNA) and binding sites, respectively, neither D I nor Dz receptor expresshTn was found to be changed in the nucleus accumbens, caudate, putamen, or substantia nigra of the cocaine-exposed subjects. Although chronic cocaine exposure can produce al-terations in dopaminergic neurotransmission, sustained compensatory changes in dopamine receptor expression do not appear to occur in the human. Key Words: Receptors, dopamine, messenger RNA, in situ hybridization, cocaine, receptor binding, human brai