Histological analysis and quantification of MPTP-induced degeneration of Tyrosinhydroxylase-positive (TH+) dopaminergic neurons in the substantia nigra (SN). A: TH-expressing dopaminergic neurons in the SN detected by immunohistochemistry. Representative coronal 40μm sections at day 10 after saline (control) or MPTP injection (MPTP) are given. Scale bar 100μm. B: MPTP-treatment (MPTP) led to a significant decrease in the numbers of TH+ dopaminergic neurons in the SN at all time points compared to controls (control). In MPTP-treated animals there was a recovery in the numbers of TH+ neurons after 70 days compared to 10 days. 10 days of levodopa-treatment had no effect on MPTP- treated groups (L-Dopa MPTP) or healthy controls (L-Dopa control). *p < 0.05, **p < 0.001 versus corresponding control (values from LSD post-hoc tests).