Fig. 2. Treatment with acid ceramidase induces AKT activation in Chang cells, but does not induce tyrosine phosphorylation or changes in tight junction proteins. (A, B) Chang cells were treated with acid ceramidase as indicated and the phosphorylation of AKT as well as tyrosine phosphorylation of cellular proteins was analyzed by western blotting. (A-D) Treatment with acid ceramidase does not alter expression levels of the tight junction proteins occludin, ZO-1 and ZO-2. Shown are representative blots (A, C) from 3 independent studies and the quantitative analysis (B, D) of the blots. Actin blots were used to normalize the samples and to show similar loading in all lanes. The quantitative data are normalized to actin. The quantitative data are mean ± SD, n=3, *p<0.05, ANOVA.