Specific binding and laterality of human extrastriatal dopamine D-2/D-3 receptors in late onset type 1 alcoholic patients

Late onset type 1 alcoholism has been suggested to be associated with decre ased dopaminergic transmission. Our hypothesis was that late onset type 1 a lcoholics have also abnormal extrastriatal dopamine D-2/D-3 receptor distri bution. We performed binding, heterogeneity and laterality analysis of extr astriatal and striatal dopamine D-2/D-3 receptors in nine late onset male a lcoholics and in 12 age-matched healthy males. A radioligand, [I-123]epidep ride was used in high resolution single-photon emission tomography (SPET). Specific binding of epidepride in the left temporal pole was significantly (P < 0.05) lower in type 1 alcoholics (0.74 +/- 0.14 ml/ml) than in control s (0.89 +/- 0.14 ml/ml). In alcoholics, there was no normal left-to-right a symmetry of the temporal cortical heterogeneity of epidepride distribution observed in control males (0.89 +/- 0.19 vs. 1.10 +/- 0.19; P < 0.05). The results suggest that the specific binding of dopamine D-2/D-3 receptors in late type 1 alcoholics is decreased and its laterality in the temporal brai n is altered from normal. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.