Role of the indirect striatopallidal pathway in mediating the ODQ-dependent reversal of STN hyperactivity.

<p>(<b>a</b>) Bar graph showing levels of CO-I staining in the STN of sham-operated and 6-OHDA lesioned rats following systemic administration of vehicle or ODQ (20 mg/kg, i.p.). ODQ significantly reduced the increase in CO-I levels observed in the STN of 6-OHDA-lesioned rats (n = 10–11 rats/group; ***<i>P<0.0005</i> as indicated, Tukey post-hoc test after significant one-way ANOVA). <i>Inset:</i> Examples of coronal sections of STN derived from CO-I staining showing the reversal effect of ODQ. (<b>b</b>) Summary of the effect of single intrastriatal infusion (0.1 µl/min for 10 min) of vehicle (0.5% DMSO in aCSF) or ODQ (50 µM) on STN CO-I staining. Intrastriatal ODQ also normalized the increased STN CO-I observed in 6-OHDA-lesioned rats (n = 5–7 rats/group; *<i>P<0.05</i>, **<i>P<0.005</i> as indicated, Tukey post-hoc test after significant one-way ANOVA). <i>Inset:</i> Sections of CO-I staining showing the reversal effect of intrastriatal ODQ on STN activity.