2012 Fiscal Year Final Research Report

The elucidation of new mechanosensor in oral mucosal epithelium

Research Project

Project/Area Number	23792107
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Morphological basic dentistry
Research Institution	Kyushu University
Principal Investigator	OU Hyou 九州大学, 大学病院, 学術研究員 (20452716)
Project Period (FY)	2011 – 2012
Keywords	ワードTRPV4 / 口腔粘膜上皮 / 低浸透圧 / Whole-cell patch clamp / Ca2+ imaging / 頬粘膜 / ATP
Research Abstract	I hypothesized that TRPV4 (Transient receptor potential cation channel subfamily V member 4) channels in oral mucosal epithelium have sensitivity of hypoosmolarity from saliva, and support the homeostasis of oral epithelial structure. I investigated the sensitivity of hypoosmolarity and it’s function using rats or TRPV4 knockout mice. I cultured primary buccal epithelial cells and confirmed TRPV4 expression in mRNA level and protein level. I took advantage of electrophysiological and Ca2+ imaging methods, and found TRPV4 induced currents and Ca2+ mobility using TRPV4 activators and hypotonic stimulation. With the same stimuli, there was a rise of ATP released from oral epithelial cells, which suggested ATP to be a mediator to peripheral nerves. I used the method of immunocytochemistry and found hypoosmolarity induced reorganization of actin, a kind of cytoskeleton. This suggested that TRPV4 supports intercellular contact