Affilié à l'Université Laval et au Centre de recherche CERVO

Striatal Neurons Expressing D1 and D2 Receptors are Morphologically Distinct and Differently Affected by Dopamine Denervation in Mice.

TitleStriatal Neurons Expressing D1 and D2 Receptors are Morphologically Distinct and Differently Affected by Dopamine Denervation in Mice.
Publication TypeJournal Article
Year of Publication2017
AuthorsGagnon D, Petryszyn S, Sanchez MG, Bories C, Beaulieu JM, De Koninck Y, Parent A, Parent M
JournalSci Rep
Volume7
Pagination41432
Date Published2017 Jan 27
ISSN2045-2322
Abstract

The loss of nigrostriatal dopamine neurons in Parkinson's disease induces a reduction in the number of dendritic spines on medium spiny neurons (MSNs) of the striatum expressing D1 or D2 dopamine receptor. Consequences on MSNs expressing both receptors (D1/D2 MSNs) are currently unknown. We looked for changes induced by dopamine denervation in the density, regional distribution and morphological features of D1/D2 MSNs, by comparing 6-OHDA-lesioned double BAC transgenic mice (Drd1a-tdTomato/Drd2-EGFP) to sham-lesioned animals. D1/D2 MSNs are uniformly distributed throughout the dorsal striatum (1.9% of MSNs). In contrast, they are heterogeneously distributed and more numerous in the ventral striatum (14.6% in the shell and 7.3% in the core). Compared to D1 and D2 MSNs, D1/D2 MSNs are endowed with a smaller cell body and a less profusely arborized dendritic tree with less dendritic spines. The dendritic spine density of D1/D2 MSNs, but also of D1 and D2 MSNs, is significantly reduced in 6-OHDA-lesioned mice. In contrast to D1 and D2 MSNs, the extent of dendritic arborization of D1/D2 MSNs appears unaltered in 6-OHDA-lesioned mice. Our data indicate that D1/D2 MSNs in the mouse striatum form a distinct neuronal population that is affected differently by dopamine deafferentation that characterizes Parkinson's disease.

DOI10.1038/srep41432
Alternate JournalSci Rep
PubMed ID28128287
PubMed Central IDPMC5269744