Effects of bilateral sham or 6-OHDA lesion and chronic daily treatment with vehicle or L-DOPA (12 mg/kg + benserazide, 15 mg/kg, sc; LD) on 5-HTir+ cells in the dorsal raphe nucleus. Bars show the effects of group on estimated total of dorsal raphe 5-HTir+ cells as determined by unbiased stereology. Differences between groups were determined by 2-way ANOVAs for lesion and treatment. The parenthesis symbolizes a main effect of lesion (p<0.05 vs. Sham). Example photos at 5X and 40X (inset) optical zoom of the dorsal raphe for (A) Sham-VEH, (B) Sham-LD, (C) Lesion-VEH, and (D) Lesion-LD are also shown.