Figure 5

Reduction of nigrostriatal neurons development in newborn Syn III ko mice is progressively recovered in adult mice. (A) Graphs show the percent changes in SN TH-positive cell numbers of Syn III ko vs. wt mice evaluated by stereology at 0, 2 and 10 months of age. Newborn mice exhibited a significant reduction of TH-positive neurons (*** p < 0.001, unpaired Student’s t-test, n = 7 per group). The analysis of TH-immunopositive area in the pr of wt and Syn III ko mice (as percent change vs. age-matched wt mice) showed that the absence of Syn III reduced this parameter in both newborn and 2-month-old mice (*** p < 0.001, ** p < 0.01, unpaired Student’s t-test, n = 3–5 animals per group). Scale bar newborn mice: 100 μm; scale bar 2 and 10 month-old mice: 150 μm. (B) Representative images showing striatal TH-positive fibers of newborn, 2-month- or 10-month-old wt and Syn III ko animals. Graphs show the percent changes in the striatal TH-positive area in the Syn III ko mice vs. wt mice (**** p < 0.0001, unpaired Student’s t-test, n = 3 animals per group). Scale bar newborn mice: 120 μm; scale bar 2 and 10 month-old mice: 200 μm. (C) Representative images showing TH-immunopositive bands from WB analysis of Syn III ko or wt mouse midbrain protein extracts. Graph shows that TH levels were significantly reduced in the midbrain of newborn (nb) and 2-month-old Syn III ko mice when compared to wt littermates. No difference in TH levels was observed at 10 months of age. Data expressed as TH protein levels normalized vs. GAPDH expression (* p < 0.05, two-way ANOVA + Bonferroni’s post-test, n = 3 animals per group). (D) WB of striatal protein extracts from Syn III ko and wt mice showed that TH protein levels did not exhibit significant changes at 0 (nb), 2 and 10 months of age. Two-way ANOVA + Bonferroni’s post-test (n = 3 animals per group).