title: Changes in transient receptor potential channels in the rat geniculate ganglion after chorda tympani nerve injury.
abstract: We reported differential expression of the transient receptor potential vanilloid 1 (TRPV1), the transient receptor potential ankyrin 1 (TRPA1), and the (TRPM8) in the geniculate ganglions (GGs) of naive rats. In medical practice, the chorda tympani nerve (CTN) is injured in some patients during middle-ear surgery, and results in tongue numbness and taste disorder. We investigated changes in the expression of these receptors in GGs after CTN injury. In naive-rat GGs, 11.4, 11.8, and 0.5% of neurons were found to express the TRPV1, the TRPA1, the TRPM8, respectively. At 3 days after CTN injury, 5.2 and 4.0% of activating transcription factor 3-immunoreactive neurons, considered as injured neurons, were found to express the TRPV1 and the TRPA1, respectively. Among activating transcription factor 3-immunonegative neurons, considered as uninjured neurons, 3.9 and 3.8% were found to express the TRPV1 and the TRPA1, respectively. The TRPM8 was not detected in GGs after CTN injury. We found decreased mRNA levels of the TRPV1 and the TRPA1 in all neurons, as well as in uninjured neurons of ipsilateral GGs after CTN injury. CTN injury changes the gene expression in GGs and may have effects on the tongue.
authors: Departments of aOtolaryngology Head and Neck Surgery bAnatomy and Neuroscience, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan.
authors: Emiko
authors: E
authors: Tatsumi
authors: Hirokazu
authors: H
authors: Katsura
authors: Kimiko
authors: K
authors: Kobayashi
authors: Hiroki
authors: H
authors: Yamanaka
authors: Kenzo
authors: K
authors: Tsuzuki
authors: Koichi
authors: K
authors: Noguchi
authors: Masafumi
authors: M
authors: Sakagami
mesh_terms: D000818:Animals; D002814:Chorda Tympani Nerve / Q000293:injuries* / Q000378:metabolism* / Q000473:pathology; D004195:Disease Models, Animal; D020220:Facial Nerve Injuries / Q000378:metabolism* / Q000473:pathology; D005830:Geniculate Ganglion / Q000378:metabolism* / Q000473:pathology; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D017207:Rats, Sprague-Dawley; D050051:Transient Receptor Potential Channels / Q000378:metabolism*
chemical_list: D050051:Transient Receptor Potential Channels