Expression of vanilloid receptor 1 in cultured fibroblast

Abstract

Although the vanilloid receptor 1 (VR1) was originally discovered on primary sensory neurons, its broad tissue expression in non-neuronal cells has been reported on. Recently, VR1 expression was clearly demonstrated in a variety of cutaneous components, such as keratinocytes, glandular epithelium, mast cells and sebocytes, except for melanocytes and fibroblasts. However, we demonstrated the VR1 expression in the cultured human skin fibroblasts as follows. Previously cloned human VR1 primers that corresponded to the expected size of 680 bp by reverse transcriptase polymerase chain reaction were identified on the fibroblasts, the same as was noted for the positive control, the HaCaT cells. A positive immunoreactivity of the VR1 was observed both on fibroblasts and on HaCaT cells by Western blotting analysis. Fibroblasts treated with capsaicin, an agonist to the VR1, induced significant changes of the membrane current and the intracellular calcium level, and these changes were antagonized by capsazepin. Capsaicin treatment also showed a positive immunocytochemistry result. Our results suggest the existence of VR1 on fibroblasts; this receptor is likely to be influenced by ligand-dependent activation.

Upregulation of Transient Receptor Potential Vanilloid Type-1 Receptor Expression in Oral Lichen Planus

“…TRPV1 receptor expression was also shown in a wide range of nonneuronal cells such as epithelial cells (keratinocytes [14,16] , gastric epithelial cells [23] , enterocytes and pneumocytes [25] ). Vascular endothelium, immune cells [26] , smooth muscle cells [25] and fibroblasts [27] also showed TRPV1 immunopositivity. In spite of extensive research in the field and accumulating immunohistochemical data, the physiological role of TRPV1 receptors in nonneuronal tissues still remains elusive [25] .…”

“…TRPV1 immunoreactivity was shown in human skin samples, including the epidermis, hair follicles, skin appendages, dermal blood vessels, Meissner corpuscles, fibroblasts and mast cells [14,27] . Isolated human keratinocytes also expressed TRPV1 receptors, and capsaicin was shown to evoke Ca 2+ uptake in keratinocyte culture [14,15] .…”

Recent Progress in Sensory Mechanism

“…In addition, the functional activation of VR1 was evaluated under treatment with agonists and antagonists to see whether a ligand-activity existed for the opening of cationic channels. The results of Kim et al 22) suggest the existence of VR1 on fibroblasts; this receptor is likely to be influenced by ligand-dependent activation.…”

“…Kim et al 22) explored VR1 expression in cultured human skin fibroblasts at the RNA and protein levels as compared with in human keratinocytes. HaCaT cells were used a positive control.…”

Investigation of the transient receptor potential vanilloid 1 (TRPV1) ion channel

“…These cells play an important role in maintaining the integrity of the immune response in skin as well as stimulating cutaneous inflammation via prostanoid and cytokine release [133].…”