کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4340804 1295810 2009 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Dopaminergic Modulation of Motor Maps in Rat Motor Cortex: An In Vivo Study
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب (عمومی)
پیش نمایش صفحه اول مقاله
Dopaminergic Modulation of Motor Maps in Rat Motor Cortex: An In Vivo Study
چکیده انگلیسی

While the primary motor cortex (M1) is know to receive dopaminergic projections, the functional role of these projections is poorly characterized. Here, it is hypothesized that dopaminergic signals modulate M1 excitability and somatotopy, two features of the M1 network relevant for movement execution and learning.To test this hypothesis, movement responses evoked by electrical stimulation using an electrode grid implanted epidurally over the caudal motor cortex (M1) were assessed before and after an intracortical injection of D1- (R-(+),8-chloro,7-hydroxy,2,3,4,5,-tetra-hydro,3-methyl,5-phenyl,1-H,3-benzazepine maleate, SCH 23390) or D2-receptor (raclopride) antagonists into the M1 forelimb area of rats. Stimulation mapping of M1 was repeated after 24 h.D2-inhibition reduced the size of the forelimb representation by 68.5% (P<0.001). Movements thresholds, i.e., minimal currents required to induce movement responses increased by 37.5% (P<0.001), and latencies increased by 35.9% (P<0.01). Twenty-4 h after the injections these effects were reversed. No changes were observed with D1-antagonist or vehicle.By enhancing intracortical excitability and signal transduction, D2-mediated dopaminergic signaling may affect movement execution, e.g. by enabling task-related muscle activation synergies, and learning.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Neuroscience - Volume 159, Issue 2, 17 March 2009, Pages 692–700
نویسندگان
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