Pharmacological characterization and anatomical distribution of the dopamine transporter in the mouse cerebellum

Abstract

We studied the binding parameters, the pharmacological profile and the anatomical distribution of the dopamine transporter in the mouse cerebellum by using the specific dopamine uptake antagonist [(3)H]GBR12935 and an antidopamine transporter monoclonal antibody. Competition experiments in cerebellar and striatal membrane preparations showed that [(3)H]GBR12935 binds to a specific binding site, sensitive to dopamine and low concentrations of mazindol. The affinity of dopamine for the cerebellar binding site was one order of magnitude lower than the affinity for the striatal binding site. Saturation experiments in cerebellar membrane preparations and thin frozen sections showed that the affinity of [(3)H]GBR12935 for this binding site is similar to its affinity for the striatal dopamine transporter. Saturable binding was lobule specific and in general was higher in the molecular layer compared to the granule cell layer. The immunohistochemical signal was mostly concentrated in the Purkinje cell layer and the cerebellar nuclei. The results suggest that the cerebellar dopamine transporter is similar but not identical to the striatal dopamine transporter and that it is present in the mouse cerebellum in a lobule and lamina specific pattern.

Dopamine D1 Receptor–Positive Neurons in the Lateral Nucleus of the Cerebellum Contribute to Cognitive Behavior

“…In rats, VTA sends glutamatergic projections to LCN, but not dopaminergic projections(13). All cerebellar nuclei are reported to have DAT-like binding, which is not blocked by norepinephrine(46, 82). Other possible sources of catecholamines in the LCN include a small population of Purkinje cells in the caudal cerebellum(83); the Zona incerta (catecholamine group A13), which has projections to the interposed cerebellar nuclei(84); and the locus ceruleus, which has been previously shown to release dopamine in the hippocampus, an area with less dopamine than cerebellar nuclei(49, 85–88).…”

Cerebellum Transcriptome of Mice Bred for High Voluntary Activity Offers Insights into Locomotor Control and Reward-Dependent Behaviors

“…Drd2 has been associated with addiction to opioids, nicotine, and cocaine [57] and mRNA encoding for Drd2 increase in response to cocaine treatment [58]. Studies of cerebellum in mice administered cocaine determined dysregulation in cerebral regions that have dopamine-signaling proteins [6, 59, 60]. In mice lacking D2 receptors, the rewarding properties of morphine were reduced [61].…”

The Cerebellar Dopaminergic System

“…Chemical neuroanatomy studies on the detection of dopaminergic neuronal elements in the cerebellum of mammals (including human) makes use of direct antisera against DA and of [ 3 H]-dopaminergic ligands (Panagopoulos et al, 1991;Panagopoulos and Matsokis, 1994) or antisera against the specific dopaminergic marker, the dopamine transporter (DAT), the plasma membrane monoamine transporter involved in DA synaptic reuptake (Table 1; Melchitzky and Lewis, 2000;Dunnet et al, 2005;Giompres and Delis, 2005;Delis et al, 2008;Kim et al, 2009;Flace et al, 2019bFlace et al, , 2020, the indirect marker of the dopaminergic neurotransmission, the dopamine and adenosine 3 ′ -5 ′ -monophosphate (cAMP)-regulated protein Mr 32,0000 (DARPP-32), a protein phosphatase-1 inhibitor involved in dopaminergic neuronal synaptic signaling (Table 1; Alder and Barbas, 1995;López et al, 2010;Nishi and Shuto, 2017), or, indirectly, by means of antisera against not elective markers for DA, such as tyrosine hydroxylase (TH), the rate-limiting enzyme DA biosynthesis, which catalyzes the conversion of L-tyrosine to L-3,4-dihydroxyphenylalanine (L-DOPA) (Table 1; Ikai et al, 1992;Fujii et al, 1994;Melchitzky and Lewis, 2000;White and Thomas, 2012) and vesicular monoamine transporter 2 (VMAT 2 ), the synaptic vesicles transporter of monoamine neurotransmitters such as DA, NA, 5-HT, and histamine (HIS) (Table 1; Kim et al, 2009;Lawal and Krantz, 2013).…”