TRP Vanilloid 2 Knock-Out Mice Are Susceptible to Perinatal Lethality But Display Normal Thermal and Mechanical Nociception

• DOI: 10.1523/jneurosci.1384-09.2011
• Publication Date: 2011-08-10T19:52:10Z
• Authors: Una Park; Nisha Vastani; Yun Guan; Srinivasa N. Raja; Martin Koltzenburg; Michael J. Caterina
• Keywords: Resiniferatoxin; Nociceptor; Knockout mouse; Mechanotransduction

TRP vanilloid 2 (TRPV2) is a nonselective cation channel expressed prominently in medium- to large-diameter sensory neurons that can be activated by extreme heat (>52°C). These features suggest TRPV2 might transducer of noxious vivo . also hypoosmolarity or cell stretch, suggesting potential roles mechanotransduction. To address the physiological functions somatosensation, we generated knock-out mice and examined their behavioral electrophysiological responses mechanical stimuli. showed reduced embryonic weight perinatal viability. As adults, surviving exhibited slightly body weight. normal over broad range temperatures punctate stimuli, both basal state under hyperalgesic conditions such as peripheral inflammation L5 spinal nerve ligation. Moreover, assays TRPV1/TRPV2 double treated with resiniferatoxin desensitize TRPV1-expressing afferents revealed no thermosensory consequences absence. In line findings, recordings from skin C-fiber C- Aδ-fiber stimuli were unimpaired absence TRPV2. The prevalence thermosensitive Aδ-fibers was too low permit comparison between genotypes. Thus, important for viability but not essential nociception hypersensitivity adult mouse.