Peripheral inflammation induces up-regulation of TRPV2 expression in rat DRG.
The transient receptor potential vanilloid subfamily member 2 (TRPV2) is a cation channel activated by temperatures above 52 degrees C. To analyze the contribution of TRPV2 to the development of inflammation-induced hyperalgesia, the expression of TRPV2 in primary sensory neurons was analyzed after intraplantar injection of complete Freund's adjuvant (CFA). Using specific antibodies, an increase in TRPV2-expressing neurons was identified after inflammation. TRPV2 expression is concentrated in a subset of medium-sized dorsal root ganglion neurons, independent of transient receptor potential vanilloid subfamily member 1 (TRPV1) expression. A similar distribution of TRPV2 was observed after inflammation. Intraplantar injection of nerve growth factor increased TRPV1 expression but not TRPV2, suggesting that induction of TRPV2 expression is driven by a mechanism distinct from that for TRPV1. Heat hyperalgesia assessment after chemical desensitization of TRPV1 by resiniferatoxin demonstrates a possible role for TRPV2 in inflammation at high temperatures (>56 degrees C). These results suggest that TRPV2 upregulation contributes to peripheral sensitization during inflammation and is responsible for pain hypersensitivity to noxious high temperature stimuli.
Shimosato
Goshun
G
Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Kamigyo-ku, Kyoto 602-8566, Japan Department of Anesthesiology Pain Research Group, Anesthesiology Department, Lausanne University Hospital (CHUV), Lausanne, Switzerland Department of Cell Biology and Morphology (DBCM), Faculty of Biology and Medicine, Lausanne University, Lausanne, Switzerland Department of Anatomy, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Amaya
Fumimasa
F
Ueda
Masashi
M
Tanaka
Yoshifumi
Y
Decosterd
Isabelle
I
Tanaka
Masaki
M
D000818:Animals; D001522:Behavior, Animal; D005620:Freund's Adjuvant; D005727:Ganglia, Spinal / Q000187:drug effects / Q000378:metabolism*; D006930:Hyperalgesia / Q000209:etiology / Q000378:metabolism*; D007249:Inflammation / Q000139:chemically induced / Q000150:complications / Q000378:metabolism*; D008297:Male; D009437:Neuralgia / Q000209:etiology / Q000378:metabolism*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D050916:TRPV Cation Channels / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
D050916:TRPV Cation Channels; C476722:Trpv2 protein, rat; D005620:Freund's Adjuvant