10.    Effect of substance P on the mesenchymal - epithelial interaction.
Long Quan Pi(1), Seok Yong Ahn(1), Ja Woong Goo(1), Soo Young Jeon(1), Tak Heon Oh(1), Sungjoo Hwang(2), Won-Soo Lee(1), 1.Department of Dermatology and Institute of Hair and Cosmetic Medicine, Yonsei University Wonju College of Medicine, Wonju, 2.Dr Hwang's Hair Clinic, Seoul, Korea

It has been well known that the epithelial–mesenchymal interaction in the hair follicle is crucial for the hair growth control. Among constituents of the skin, hair follicle is an organ with the highest density of nerve fibers distributed. Recently, it has been reported that neuropeptides play important roles in the hair growth and hair cycle change, which are secreted by nerve fibers. In the previous study conducted by us, we examined mRNAs corresponding to FGF-7, IGF-1, VEGF, IL-1beta, IL-1alpha, p53, caspase-3, after culturing hair follicle dermal papilla(DP) cells and outer root sheath(ORS) cells pretreated with substance P(SP). As results, in DP cell culture, the expression of IL-1beta less than control, but in ORS cells was not shown. From the results, We can suppose signal(s) from the DP cells may influence the ORS cells. In this study, we examined the effect of SP on the mesenchymal-epithelial interaction in the human hair follicle. ORS cells were cultured in only dermal papilla conditioned medium(DPCM) or DPCM treated with SP, then observed the expression change of the ORS cell proliferation and gene expression. As results, the proliferation of ORS cells continuously increased when they were cultured in the DPCM treated with SP for 48 hours. It may concluded that various growth factors exist in the DPCM treated with SP, and influenced the proliferation of outer root sheath cells.