| First Author | Suzuki A | Year | 2016 |
| Journal | Mol Pain | Volume | 12 |
| PubMed ID | 27030715 | Mgi Jnum | J:323647 |
| Mgi Id | MGI:6875344 | Doi | 10.1177/1744806916633206 |
| Citation | Suzuki A, et al. (2016) Regulation of transient receptor potential vanilloid 1 expression in trigeminal ganglion neurons via methyl-CpG binding protein 2 signaling contributes tongue heat sensitivity and inflammatory hyperalgesia in mice. Mol Pain 12 |
| abstractText | BACKGROUND: Pain hypoalgesia has been reported in Rett syndrome patients, a severe neurodevelopmental disorder which can be attributed to mutations in the methyl-CpG binding protein 2 (MeCP2). Here, we examined the role of MeCP2 signaling in tongue heat sensitivity in the normal and inflamed state using Mecp2 heterozygous (Mecp2(+/-)) mice. RESULTS: Heat hypoalgesia of the tongue occurred in Mecp2(+/-) mice and submucosal injection of complete Freund's adjuvant into the tongue produced a long-lasting heat hyperalgesia at the inflamed site in wild-type mice but not in Mecp2(+/-) mice. Transient receptor potential vanilloid 1 was expressed in a large number of MeCP2-immunoreactive trigeminal ganglion neurons innervating the tongue in both wild-type and Mecp2(+/-) mice (70.9% in wild type; 72.1% in Mecp2(+/-)). The number of transient receptor potential vanilloid 1-immunoreactive trigeminal ganglion neurons innervating the tongue was smaller in Mecp2(+/-) mice relative to wild-type mice (30.5% in wild type; 20.2% in Mecp2(+/-)). Following complete Freund's adjuvant injection, the number of transient receptor potential vanilloid 1- and MeCP2-immunoreactive trigeminal ganglion neurons innervating the tongue, as well as MeCP2 protein expression in trigeminal ganglion, was significantly increased in wild-type mice but not in Mecp2(+/-) mice. Additionally, tongue heat hyperalgesia following complete Freund's adjuvant injection was completely suppressed by the administration of SB366791, a transient receptor potential vanilloid 1 antagonist, in the tongue. CONCLUSIONS: These findings indicate that tongue heat sensitivity and hypersensitivity are dependent on the expression of transient receptor potential vanilloid 1 which is regulated via MeCP2 signaling in trigeminal ganglion neurons innervating the tongue. |
