Fig. 4. Western blot analysis showing levels of p38 mitogen-activated protein kinase (MAPK) (  A .1) and phosphorylated p38 MAPK (  A .2) after 5 min of reoxygenation alone (control) or in the presence of 5 min of 6% desflurane (desflurane). Western blot analysis was performed using specific antibodies against p38 MAPK, phospho-p38 MAPK, and β-tubulin. Histograms depicting the expression level of p38 MAPK (  B .1) and the variation of phosphorylation of p38 MAPK (  B .2) in control and 6% desflurane groups. The relative p38 MAPK protein levels were calculated by averaging the results obtained from five independent experiments and were normalized to the β-tubulin control in each group. Densitometry analysis is expressed in arbitrary units. Data are mean ± SD. NS = not significant.