Figure 9

Differential patterns of α-synuclein immunoreactivity after PQ (10 mg/kg b.w.) treatment. α-Synuclein immunolocalization in SN, FC and hippocampus (A, B and C, respectively). (D) Densitometric analysis of western blot α-synuclein in SN, FC and hippocampus. (A): α-Synuclein immunopositivity was dense in neuritic areas of SN in controls (a). α-Synuclein immunopositivity decreased in neuritic areas, and a few pigmented nuclear structures (putative Lewy bodies) appeared (black arrows) in SN of PQ-treated animals (b). (B): α-Synuclein immunoreactivity in neuritic areas of FC in PQ-treated and control animals. Large numbers of pigmented nuclear structures (putative Lewy bodies) appeared (black arrows) in FC of PQ-treated brain (b), compared to vehicle-treated controls (a). (C): Non-nucleated areas (neuritic portions) but not nucleated areas, of hippocampus showed α-synuclein immunopositivity in both control and treated animals. Dense α-synuclein immunoreactivity appeared in non-nucleated areas of hippocampal regions CA3 and CA1 (b, d, respectively) in PQ-treated mouse brain compared to controls (a, c, respectively). A few pigmented deposits (putative Lewy bodies) were found in non-nucleated areas of hippocampal regions of PQ-treated animals, but not in respective controls. (D): Densitometric analysis of western blots indicate that expression levels of α-synuclein decreased significantly in SN, increased significantly in hippocampus and were unaltered in FC of PQ-treated animals, compared to controls. β-Actin was used as a reference control. Data are presented as mean ± SEM. (n = 3). Asterisks (*) represent significant differences, with p < 0.05 (Student's t-test) in densitometric analyses. Magnification of IHC images is 40× and the scale bars = 40µm.