Altered thermal selection behavior in mice lacking transient receptor potential vanilloid 4.
Transient receptor potential vanilloid 4 (TRPV4), a cation channel responsive to hypotonicity, can also be activated by warm temperatures. Moreover, TRPV4-/- mice reportedly exhibit deficits in inflammation-induced thermal hyperalgesia. However, it is unknown whether TRPV4 or related transient receptor potential channels account for warmth perception under injury-free conditions. We therefore investigated the contribution of TRPV4 to thermosensation and thermoregulation in vivo. On a thermal gradient, TRPV4-/- mice selected warmer floor temperatures than wild-type littermates. In addition, whereas wild-type mice failed to discriminate between floor temperatures of 30 and 34 degrees C, TRPV4-/- mice exhibited a strong preference for 34 degrees C. TRPV4-/- mice also exhibited prolonged withdrawal latencies during acute tail heating. TRPV4-/- and wild-type mice exhibited similar changes in behavior on a thermal gradient after paw inflammation. Circadian body temperature fluctuations and thermoregulation in a warm environment were also indistinguishable between genotypes. These results demonstrate that TRPV4 is required for normal thermal responsiveness in vivo.
Lee
Hyosang
H
Department of Biological Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA.
Iida
Tohko
T
Mizuno
Atsuko
A
Suzuki
Makoto
M
Caterina
Michael J
MJ
D000818:Animals; D001169:Arthritis, Experimental / Q000503:physiopathology / Q000523:psychology; D001833:Body Temperature Regulation; D027682:Cation Transport Proteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D002940:Circadian Rhythm; D005620:Freund's Adjuvant / Q000633:toxicity; D005838:Genotype; D006358:Hot Temperature; D006799:Housing, Animal; D007473:Ion Channels / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010468:Perceptual Disorders / Q000235:genetics* / Q000503:physiopathology; D010641:Phenotype; D011930:Reaction Time; D050916:TRPV Cation Channels
D027682:Cation Transport Proteins; D007473:Ion Channels; D050916:TRPV Cation Channels; C486576:Trpv4 protein, mouse; D005620:Freund's Adjuvant