title: Modulation of paratrigeminal nociceptive neurons following temporomandibular joint inflammation in rats.
abstract: To evaluate the involvement of paratrigeminal nucleus (Pa5) nociceptive neurons in temporomandibular joint (TMJ) inflammation-induced pain and its autonomic correlates, we conducted behavioral, single unit recording and Fos immunohistochemical studies in anesthetized rats. Nocifensive behaviors to mechanical, heat or cold stimulation of the lateral face over the TMJ region were significantly enhanced in the TMJ-inflamed rats for 10-14 days after injection of complete Freund's adjuvant (CFA) into the TMJ and gradually decreased at the end of the 14-day observation period. Lowering of the nocifensive threshold in TMJ-inflamed rats lasted longer in vagus nerve-transected rats than vagus nerve-intact rats. A large number of Fos-like immunoreactive (LI) cells were observed in the Pa5, and half of them were retrogradely labeled with Fluorogold (FG) injected into the parabrachial nucleus. Background activity of Pa5 wide dynamic range and nociceptive specific neurons was significantly higher in the TMJ-inflamed rats when compared with controls. Responses to mechanical stimuli were significantly higher in NS neurons in the TMJ-inflamed rats. All thermal responsive Pa5 neurons were exclusively sensitive to cold and the response to cold was significantly higher in the TMJ-inflamed rats compared with control rats. Vagus nerve stimulation significantly decreased responses to mechanical and cold stimuli as well as the background activity in TMJ-treated rats but not in TMJ-untreated rats. The present findings suggest that populations of Pa5 neurons are nociceptive and involved in TMJ inflammation-induced pain as well as in autonomic processes related to TMJ pain.
authors.affiliation: Department of Orofacial Pain Management, Tokyo Medical and Dental University, Bunkyo-ku, Yushima, Tokyo 113-8549, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yamazaki
authors.forename: Ke
authors.initials: K
authors.lastname: Ren
authors.forename: Masahiko
authors.initials: M
authors.lastname: Shimada
authors.forename: Koichi
authors.initials: K
authors.lastname: Iwata
mesh_terms: D000276:Adjuvants, Immunologic; D000818:Animals; D003080:Cold Temperature; D004558:Electric Stimulation; D005620:Freund's Adjuvant; D006358:Hot Temperature; D006930:Hyperalgesia / Q000276:immunology / Q000503:physiopathology; D007249:Inflammation / Q000139:chemically induced / Q000276:immunology / Q000503:physiopathology; D008297:Male; D009474:Neurons / Q000378:metabolism; D009619:Nociceptors / Q000502:physiology*; D017288:Pain Threshold; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013705:Temporomandibular Joint Disorders / Q000276:immunology* / Q000503:physiopathology*; D014278:Trigeminal Nuclei / Q000166:cytology / Q000502:physiology*; D014630:Vagus Nerve / Q000502:physiology
chemical_list: D000276:Adjuvants, Immunologic; D016760:Proto-Oncogene Proteins c-fos; D005620:Freund's Adjuvant
references.citation: Auton Neurosci. 2003 Apr 30;105(1):25-34
references.pmid: 12742188
references.citation: J Comp Neurol. 1995 Jun 5;356(3):444-56
references.pmid: 7642805
references.citation: J Neurosci. 1998 Oct 1;18(19):8056-64
references.pmid: 9742172
references.citation: Pain. 2001 Nov;94(2):185-191
references.pmid: 11690732
references.citation: Exp Brain Res. 2003 Oct;152(3):307-16
references.pmid: 12898097
references.citation: J Orofac Pain. 2004 Spring;18(2):108-13
references.pmid: 15250430
references.citation: Brain Behav Immun. 2007 Jul;21(5):634-41
references.pmid: 17055698
references.citation: J Neurophysiol. 1988 Dec;60(6):2180-95
references.pmid: 3236065
references.citation: Brain Res. 2006 Feb 9;1072(1):99-109
references.pmid: 16442086
references.citation: Somatosens Mot Res. 1990;7(2):153-83
references.pmid: 2378191
references.citation: Pain. 2006 Nov;125(1-2):65-73
references.pmid: 16762506
references.citation: J Neurophysiol. 1993 May;69(5):1530-40
references.pmid: 8389827
references.citation: Pain. 2000 May;86(1-2):81-5
references.pmid: 10779664
references.citation: Brain Res Mol Brain Res. 1999 Apr 6;67(1):87-97
references.pmid: 10101236
references.citation: Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1996 Nov;82(5):496-500
references.pmid: 8936511
references.citation: Pain. 2005 Sep;117(1-2):58-67
references.pmid: 16043292
references.citation: Exp Brain Res. 2003 Jan;148(2):211-8
references.pmid: 12520409
references.citation: Cranio. 1989 Apr;7(2):137-43
references.pmid: 2611904
references.citation: J Neurophysiol. 2007 Dec;98(6):3242-53
references.pmid: 17928557
references.citation: Brain Res Brain Res Rev. 1992 May-Aug;17(2):77-99
references.pmid: 1327371
references.citation: J Neurophysiol. 1999 Sep;82(3):1244-53
references.pmid: 10482744
references.citation: Headache. 1989 Apr;29(4):229-32
references.pmid: 2714973
references.citation: Pain. 2002 Mar;96(1-2):205-13
references.pmid: 11932076
references.citation: J Oral Sci. 2005 Jun;47(2):65-9
references.pmid: 16050485
references.citation: Cells Tissues Organs. 2001;169(3):238-47
references.pmid: 11455119
references.citation: Pain. 1991 Jan;44(1):81-87
references.pmid: 2038494
references.citation: J Dent Res. 2002 Apr;81(4):279-83
references.pmid: 12097314
references.citation: Pain. 1996 Apr;65(1):101-109
references.pmid: 8826496
references.citation: Pain. 1983 Jun;16(2):109-110
references.pmid: 6877845
references.citation: Brain Res Mol Brain Res. 1992 May;13(4):301-12
references.pmid: 1320720
references.citation: J Comp Neurol. 1999 Sep 20;412(2):276-91
references.pmid: 10441756
references.citation: Pain Res Manag. 2005 Autumn;10(3):145-52
references.pmid: 16175250
references.citation: Eur J Pain. 2005 Feb;9(1):87-93
references.pmid: 15629879
references.citation: Pain. 1995 Jul;62(1):19-38
references.pmid: 7478705
references.citation: Pain. 1988 Jan;32(1):77-88
references.pmid: 3340425
references.citation: Am J Med. 2003 Aug 18;115 Suppl 3A:31S-38S
references.pmid: 12928072
references.citation: Pain. 1992 Jan;48(1):53-60
references.pmid: 1738575
references.citation: Auton Neurosci. 2002 Jun 28;98(1-2):70-4
references.pmid: 12144045
references.citation: Pain. 2006 Jun;122(3):235-244
references.pmid: 16616416
references.citation: Auton Neurosci. 2001 Dec 10;94(1-2):14-24
references.pmid: 11775703
references.citation: Brain Res. 1995 Apr 24;678(1-2):127-39
references.pmid: 7620882
references.citation: Neuroscience. 1995 Dec;69(3):939-53
references.pmid: 8596661
references.citation: J Neurosci. 2006 Apr 19;26(16):4308-17
references.pmid: 16624951
references.citation: Arch Oral Biol. 2005 Jan;50(1):73-9
references.pmid: 15598419
references.citation: Clin Exp Hypertens. 2008 Jan;30(1):45-55
references.pmid: 18214733
references.citation: J Oral Maxillofac Surg. 1990 Sep;48(9):968-71
references.pmid: 2168477
references.citation: Can J Physiol Pharmacol. 2004 Jul;82(7):474-84
references.pmid: 15389294