Summary After the cloning of the dopamine D 1 and D 2 re- ceptors (13), several additional dopamine recep- tors were identified. These new subtypes included the D 3 and D 4 receptors, which are similar to D 2 , and the D 5 receptor, which is similar to D 1 (46). Al- though most studies have focused on the role of dopamine D 1 and D 2 receptors in mediating the ad- dictive liability of drugs, the lack of selective phar- macological tools has significantly hampered this particular field of research. In contrast, recent studies using selective competitive antagonists have shown that the dopamine D 3 receptor is involved in drug- seeking behavior. The present review is intended to highlight a new, promising area in alcohol research that focuses on the role of the dopamine D 3 recep- tor in the addictive properties of ethanol. © 2004 Prous Science. All rights reserved. ROLE OF DOPAMINE D 3 RECEPTORS IN THE ADDICTIVE PROPERTIES OF ETHANOL Christian A. Heidbreder 1 , Michela Andreoli 1 , Clara Marcon 1 , Panayotis K. Thanos 2 , Charles R. Ashby, Jr. 3 and Eliot L. Gardner 4 1 Center of Excellence for Drug Discovery in Psychiatry, GlaxoSmithKline Pharmaceuticals, Verona, Italy; 2 Medical Department, Brookhaven National Laboratory, Upton, New York, USA; 3 Department of Pharmaceutical Sciences, College of Pharmacy and Allied Health Professions, Saint Johns University, Jamaica, New York, USA; 4 Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland, USA Drugs of Today 2004, 40 (4): 355-365 Copyright © 2004 PROUS SCIENCE CCC: 0025-7656/2004 CONTENTS Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 356 Alcoholism: The magnitude of the problem . . . . . . . . . . . . . . . . . . . . . . 356 Effect of alcohol on dopamine function in the mesolimbic reward system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 356 Localization of the dopamine D 3 receptor: Relevance to the mesolimbic dopamine systems and the rewarding properties of alcohol. . . . . . . . . . 357 Gene polymorphisms at the dopamine D 3 receptor and alcoholism . . . . . . 358 Functional pharmacological studies with dopamine D 3 ligands and animal models of alcohol-taking and -seeking behaviors. . . . . . . . . 359 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361 Correspondence: Christian A. Heidbreder, Department of Biology, Center of Excellence for Drug Discovery in Psy- chiatry, GlaxoSmithKline Pharmaceuticals, Via A. Fleming 4, 37135 Verona, Italy. Tel.: +39-045-921-9769; FAX: +39- 045-921-8047. E-mail: Christian_A_Heidbreder@gsk.com