BRAIN DOPAMINE TRANSPORTER - GENDER DIFFERENCES AND EFFECT OF CHRONIC HALOPERIDOL

Gender differences and the effect of chronic haloperidol on the rat brain dopamine transporter is reported. The density of striatal dopamine transporter sites labelled with [H-3]GBR 12935, and of substantia nigra dopamine transporter mRNA measured by in situ hybridization were higher in female compared to male rats whereas striatal D2 specific binding labelled with [H-3]spiperone was not significantly higher. Daily haloperidol treatment (1 mg/kg, i.p.) for 21 days increased striatal [H-3]spiperone specific binding but left unchanged striatal [H-3]GBR 12935 binding density and affinity as well as substantia nigra dopamine transporter mRNA levels. A reduce clearance rate of dopamine in the striatum after acute and chronic haloperidol was previously reported; the present results indicate that this may occur without changes in the sites of dopamine transport or in gene expression of this transporter.