Quantitative autoradiographic analysis of dopamine D₃ receptors, DAT and DTBZ densities in the globus pallidus.

<p>Autoradiograms show total binding of 1.44 nM [³H]SCH23390, 2.50 nM [³H]raclopride, 3.54 nM [³H]<b>WC-10</b>, 2.19 nM [³H]WIN35428, 4.53 nM [³H]DTBZ (A), and nonspecific binding in presence of 1 µM (+) butaclamol (for [³H]SCH23390), 1 µM <i>S</i>(-)-eticlopride (for [³H]raclopride and [³H]<b>WC-10</b>), 1 µM nomifensine (for [³H]WIN35428) and 1 µM <i>S</i>(-)-tetrabenazine (for [³H]DTBZ) (B) in the globus pallidus of aged human brain sections. The adjacent section shows cresyl violet staining to identify related anatomical structures (C). [³H]Microscale standards (ranging from 0 to 36.3 nCi/mg) were also counted (D). Quantitative analysis of dopamine D₁, D₂, and D₃ receptors, DAT and DTBZ densities (fmol/mg) and the dopamine D₂ ∶ D₃ receptor density ratio in human globus pallidus are shown in E and F, respectively. The numbers 1 through 5 designate the following CNS anatomical regions: 1: Putamen; 2: Caudate; 3: Globus pallidus external part (GPe); 4: Globus pallidus internal part (GPi); 5: Internal capsule (IC). *p<0.05 compared to GPe.