title: Temperature-sensitive transient receptor potential channels in corneal tissue layers and cells.
abstract: We here provide a brief summary of the characteristics of transient receptor potential channels (TRPs) identified in corneal tissue layers and cells. In general, TRPs are nonselective cation channels which are Ca(2+) permeable. Most TRPs serve as thermosensitive molecular sensors (thermo-TRPs). Based on their functional importance, the possibilities are described for drug-targeting TRP activity in a clinical setting. TRPs are expressed in various tissues of the eye including both human corneal epithelial and endothelial layers as well as stromal fibroblasts and stromal nerve fibers. TRP vanilloid type 1 (TRPV1) heat receptor, also known as capsaicin receptor, along with TRP melastatin type 8 (TRPM8) cold receptor, which is also known as menthol receptor, are prototypes of the thermo-TRP family. The TRPV1 functional channel is the most investigated TRP channel in these tissues, owing to its contribution to maintaining tissue homeostasis as well as eliciting wound healing responses to injury. Other thermo-TRP family members identified in these tissues are TRPV2, 3 and 4. Finally, there is the TRP ankyrin type 1 (TRPA1) cold receptor. All of these thermo-TRPs can be activated within specific temperature ranges and transduce such inputs into chemical and electrical signals. Although several recent studies have begun to unravel complex roles for thermo-TRPs such as TRPV1 in corneal layers and resident cells, additional studies are needed to further elucidate their roles in health and disease.
authors.affiliation: Department of Ophthalmology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Mergler
authors.forename: Monika
authors.initials: M
authors.lastname: Valtink
authors.forename: Sumioka
authors.initials: S
authors.lastname: Takayoshi
authors.forename: Yuka
authors.initials: Y
authors.lastname: Okada
authors.forename: Masayasu
authors.initials: M
authors.lastname: Miyajima
authors.forename: Shizuya
authors.initials: S
authors.lastname: Saika
authors.forename: Peter S
authors.initials: PS
authors.lastname: Reinach
mesh_terms: D001831:Body Temperature / Q000502:physiology; D015220:Calcium Channels / Q000378:metabolism*; D003315:Cornea / Q000378:metabolism*; D006801:Humans; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D000074025:TRPA1 Cation Channel; D050053:TRPM Cation Channels / Q000378:metabolism*; D050916:TRPV Cation Channels / Q000378:metabolism*; D050051:Transient Receptor Potential Channels / Q000378:metabolism*
chemical_list: D015220:Calcium Channels; D009419:Nerve Tissue Proteins; D000074025:TRPA1 Cation Channel; C473350:TRPA1 protein, human; D050053:TRPM Cation Channels; C425966:TRPM8 protein, human; D050916:TRPV Cation Channels; D050051:Transient Receptor Potential Channels