Figure 8

Differential patterns of immunoreactivity of dopaminergic neuronal markers in brain after PQ (10 mg/kg b.w.) treatment. Immunoreactive localization of TH was observed in SN, FC and different parts of the hippocampus (A, B and C, respectively). Densitometric analysis of western blots for FOX3, TH and DOPA decarboxylase (D, E and F respectively) was performed to assess the status of dopaminergic neurons in SN, FC and hippocampus. (A): TH-immunopositive neuronal cells (pigmented) and neurites were decreased in SN of PQ-treated mice (b) compared to controls (a). (B): The cellular localization of TH immunoreactivity shifted from nucleated to non-nucleated neuritic areas in FC in PQ-treated animals (b) compared to controls (a). (C): TH immunopositivity appeared in non-nucleated neuritic areas of the hippocampus (dentate gyrus, CA3 and CA1) in PQ-treated animals (b, d, f respectively) compared to TH immunolocalization in nucleated areas in controls (a, c and e respectively). (D and E): Expression levels of TH decreased in SN, FC and hippocampal areas of PQ-treated mice compared to respective controls (E). PQ treatment caused significant decreases in expression levels of FOX 3 (D) and DOPA decarboxylase (F) in SN and FC, without any changes of those parameters in hippocampus, compared to respective controls. β-Actin was used as a reference control in the western blots. Data are presented as mean ± SEM. (n = 3). Asterisks (*) represent significant differences at a level of p < 0.05 (Student's t-test) for the densitometric analyses. Magnification of IHC images is 40×, and the scale bars = 40µm.