title: TRPA1 detects environmental chemicals and induces avoidance behavior and arousal from sleep.
abstract: Detecting threats and escaping before serious confrontations are important for animals to avoid danger and death. Transient receptor potential ankyrin 1 (TRPA1), a member of the TRP superfamily, is expressed in a subset of sensory neurons and mediates nociception evoked by pungent chemicals. Using behavioral testing, we found that TRPA1 knockout mice failed to avoid entering a chamber filled with vapor of formalin, allyl isothiocyanate, and acrolein. The avoidance behavior was blocked by nasal but not subcutaneous administration of a blocker to TRPA1. We also found that TRPA1 knockout mice did not wake when exposed to formalin during sleep. Additionally, the spinal trigeminal nucleus, the first relay neurons of the trigeminal system, showed massive expression of c-Fos after a brief (3 min) exposure to formalin vapor. TRPA1 seems to be a sentinel for environmental chemicals and induces avoidance behaviors and waking by way of the trigeminal system.
authors.affiliation: 1] Departments of Physiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan [2] Departments of Anesthesiology and Critical Care Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Yonemitsu
authors.forename: Chiharu
authors.initials: C
authors.lastname: Kuroki
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Takahashi
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Mori
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kanmura
authors.forename: Hideki
authors.initials: H
authors.lastname: Kashiwadani
authors.forename: Youichirou
authors.initials: Y
authors.lastname: Ootsuka
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Kuwaki
mesh_terms: D000818:Animals; D001143:Arousal; D001362:Avoidance Learning; D001522:Behavior, Animal; D059647:Gene-Environment Interaction; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D011984:Sensory Receptor Cells / Q000378:metabolism; D012890:Sleep; D000074025:TRPA1 Cation Channel; D050051:Transient Receptor Potential Channels / Q000235:genetics* / Q000378:metabolism*; D014279:Trigeminal Nucleus, Spinal / Q000378:metabolism
chemical_list: D000074025:TRPA1 Cation Channel; D050051:Transient Receptor Potential Channels; C475685:Trpa1 protein, mouse