6-OHDA-lesion-related alterations in spontaneous activity of MSNs are rescued by either chronic l-DOPA or pramipexole treatment. A, B, Bar graphs show the averaged values of the frequency (A) and amplitude (B) of spontaneous events recorded in MSNs from the different experimental groups: control (CTRL), 6-OHDA-lesioned rats (6-OHDA), l-DOPA-treated rats, 0.3 mg/kg pramipexole-treated rats, and 1 mg/kg pramipexole-treated rats (n = 8 CTRL vs n = 6 6-OHDA, *p < 0.05 frequency, **p < 0.01 amplitude; n = 14 l-DOPA vs 6-OHDA, #p < 0.05 frequency, ###p < 0.001 amplitude; n = 9 pramipexole 0.3 mg/kg vs 6-OHDA, #p < 0.05 frequency, #p < 0.05 amplitude, n = 6 pramipexole 1 mg/kg vs 6-OHDA, #p < 0.05 frequency, #p < 0.05 amplitude; one-way ANOVA with Bonferroni comparison). C, Representative traces from whole-cell patch-clamp experiments showing glutamatergic sEPSCs recorded from MSNs in control condition (upper trace) and in all the other groups of animals studied.