Protein expression of IKKα, IKKβ, p-IKKα/β, IκBα and p-IκBα in the fibroblasts of the co-culture system. A. Western blot results showing the expression changes of these proteins by SP. B. Histogram showing the relative intensity of bands to Control in western blot (N=3). **P<0.01. SP, substance P. IκBα, inhibitor of NF-κB alpha. p-IκBα, phosphorylated IκBα. IKKα, IκB kinase alpha. IKKβ, IκB kinase beta.