The human dopamine D2(Longer) receptor has a high-affinity state and inhibits adenylyl cyclase

Brain dopamine D2 receptors are the main targets for antipsychotic and anti -Parkinsonian drugs. The dopamine D2 receptor has three forms, D2(Short), D 2(Long) and D2(Longer), D2(Longer) is a newly found splice variant which co ntains two additional amino acids (valine and glutamine) in the third cytop lasmic loop of the receptor. To determine whether D2(Longer) was functional , the cDNA was transfected into CHO cells. D2(Longer) revealed a high-affin ity state for dopamine (similar to 1.5 nM), and mediated dopamine-inhibited adenylyl cyclase. (C) 2000 Elsevier Science B.V. All rights reserved.