Mechanisms of calcitriol action in fetal ASM. Calcitriol blunted TNFα-induced phosphorylation of (A) ERK but not (B) p38, (C) JNK phosphorylation, (D) nuclear translocation of the p50 and p65 NFκB subunits, and TGFβ-induced (E) Smad2 phosphorylation. Western blots are representative results from independent experiments using at least 3 individual samples. Data are presented as mean ± SEM, n=3 samples, p<0.05. * indicates significant difference from control.