FIGURE 7.

The effects of protein phosphatase 2A/1 and proteasome inhibitors on the levels of Ser-129-phosphorylated a-Syn in rat primary cortical neurons. A, 21-day cultured primary neurons were incubated in fresh medium containing either 0.1% DMSO, 10 μm MG132, 10 μm lactacystin, or 10 nm OA for 4 h. The cell lysates (50 μg/lane) were loaded on SDS-PAGE and analyzed by immunoblotting (IB) with psyn 64 and Syn-1 antibodies. For loading control, the same amounts of samples were immunoblotted with anti-β-actin antibody. Experiments were performed four times. Representative blots are shown. B, quantitative analysis of the alteration in the expression levels of Ser-129-phosphorylated a-Syn in the cells. Relative ratios of the band intensity of Ser-129-phosphorylated a-Syn to β-actin and total a-Syn to β-actin are shown by normalizing to the starting material. Data represent means ± S.D., and the p values (*, p < 0.05; **, p < 0.01) are shown.