Rescue of lipid accumulation in 51KO cells by the p38 kinase inhibitor PD169316. A, WT and 51KO MEFs were differentiated by treatment with the DIIR mixture in the absence (D) or presence of PD169316 inhibitor (D-PD) specific to p38 MAPK, followed by staining for lipid content with Nile Red. Phase-contrast images are also shown. Images of stained adipocytes are representative of 3 independent experiments B, Optical density quantitation of intracellular lipid in cells treated in panel A (±SEM; n = 3). Statistical differences are indicated as follows: *, P > .05; **, P > .01; ***, P > .001; the same parameters apply for # and ∧ symbols. *, WT vs WT; #, 51KO vs 51KO; ∧, WT vs 51KO.