Figure 2.

Peroxynitrite selectively regulates human and mouse MD-Schwann cell survival. A and B, survival of: mouse (A) and human WT- and MD-Schwann cells (B) was assessed by nuclear staining with crystal violet, as described under “Experimental procedures,” after 48 and 96 h of incubation in the absence and presence of the NOS inhibitor l-NAME (1, 2.5, and 5 mm), the superoxide and peroxynitrite scavenger FeTCPP (10 and 50 μm), and urate (10, 50, and 100 μm), a natural scavenger of peroxynitrite-derived radicals. Cell survival is expressed as percentage of untreated control (n = 6–7 with 8 replicates). C, representative IR Western blotting for nitrotyrosine of MD-Schwann cells incubated in the absence and presence of l-NAME (2.5 mm), FeTCPP (50 μm), and urate (100 μm) for 48 h. On the right, quantitation of the corresponding bands normalized against α-tubulin. Columns represent the mean ± S.D. (n = 3–5) expressed relative to untreated control. *, p < 0.01 versus untreated control by Kruskal Wallis test followed by Dunn's post test.