Affiliated with Université Laval & CERVO Research Centre

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

Publication Type:

Journal Article


Sci Rep, Volume 7, p.41432 (2017)


Animals, Dendritic Spines, Denervation, Dopamine, Dynorphins, Enkephalins, Mice, Transgenic, Neostriatum, Neurons, Nucleus Accumbens, Oxidopamine, Receptors, Dopamine D1, Receptors, Dopamine D2, Substantia Nigra, Tyrosine 3-Monooxygenase, Ventral Tegmental Area


<p>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 D or D dopamine receptor. Consequences on MSNs expressing both receptors (D/D MSNs) are currently unknown. We looked for changes induced by dopamine denervation in the density, regional distribution and morphological features of D/D MSNs, by comparing 6-OHDA-lesioned double BAC transgenic mice (Drd1a-tdTomato/Drd2-EGFP) to sham-lesioned animals. D/D 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 D and D MSNs, D/D MSNs are endowed with a smaller cell body and a less profusely arborized dendritic tree with less dendritic spines. The dendritic spine density of D/D MSNs, but also of D and D MSNs, is significantly reduced in 6-OHDA-lesioned mice. In contrast to D and D MSNs, the extent of dendritic arborization of D/D MSNs appears unaltered in 6-OHDA-lesioned mice. Our data indicate that D/D MSNs in the mouse striatum form a distinct neuronal population that is affected differently by dopamine deafferentation that characterizes Parkinson's disease.</p>