Stimulation of p38 by mitogens and cellular stress. (A, B) Serum-starved NIH3T3 cells were treated with FCS or bFGF (A), anisomycin (10 μg/ml) or sorbitol (400 mM) (B) and total cell extracts prepared at the indicated time points. Western blot analysis was performed using a phospho-specific (T180/Y182) anti-p38-antibody. The blots were stripped and reprobed with an anti-p38-antibody to control equal loading. Data from a single experiment are shown. Similar results were obtained in three independent experiments.