EXPRESSION OF A SINGLE DOPAMINE TRANSPORTER CDNA CAN CONFER 2 COCAINE BINDING-SITES

RADIOLABELED cocaine analogs can bind to low and high affinity sites on striatal dopamine transporters (DAT). Recently, a cDNA encoding a rat brain dopamine transporter pDAT1 has been cloned. COS cells transfected with the pDAT1 in a eukaryotic expression vector express both a high (K(D) = 3.4 nM) and low affinity (K(D) = 163.6 nM) cocaine binding sites, suggesting that both sites are provided by a single gene product.