Fig. 1.

Hypoxia-induced activation of p38. Cerebral microvascular endothelial cell (CMEC) monolayers were exposed to 19% O₂ (normoxic control) or 7% or 2% O₂ in HEPES-DMEM for 5, 30, 60, or 120 min. Cell lysates were prepared and subjected to Western blot analysis using antibodies that recognize only phosphorylated (activated) p38 (p-p38) or p-p38 and nonphosphorylated p38 (i.e., total p38 protein). A: representative Western blots. Bands shown for p38 and p-p38 are ∼38 kDa. B: abundance of p-p38. Values at 5–120 min are kinase abundances for 7% and 2% O₂ exposures relative to internal normoxic control (0 min) for each experiment and are means ± SE of 8 and 7 separate experiments for 7% and 2% O₂, respectively. *Significantly different from normoxic control, P < 0.05 by 1-tailed paired t-test.