Figure 1. Activation of p38 MAPK and STEP during MCAO and reperfusion. SD (a–e) and Wistar (g–j) rats were subjected to MCAO for (a, b, g, h) 15, 30, 60, or 90 min or (d, e, i, j) 90 min followed by reperfusion for 3, 6, or 12 h. Tissue punches from the ipsilateral striatum were analyzed by immunoblotting with (a, d, g, i) anti-phospho-p38 MAPK (top) and reprobed with anti-p38 MAPK (bottom); (b, e, h, j) anti-STEP antibody (top, STEP61; middle, STEP33) and then reprobed with anti-tubulin antibody (bottom). c, STEP was immunoprecipitated from striatal lysates (sham and 90 min MCAO) using anti-STEP antibody and processed for immunoblot analysis with p-ser 221 antibody (top). The blot was then reprobed with anti-STEP antibody (bottom). f, SD rats were subjected to 90 min MCAO followed by reperfusion for 6 h and then processed for immunohistochemistry with anti-phospho-p38 MAPK and NeuN antibodies and DAPI staining. Bar diagrams represent mean ± SEM obtained from 4 animals per group. a, *p < 0.01, from 15 min MCAO. **p < 0.001, from 15 min MCAO. b, *p < 0.001, from phosphorylated STEP in sham. #p < 0.001, from dephosphorylated form of STEP in sham. d, *p < 0.001, from I/R-6 h. e, *p < 0.05, from I/R-6 h.