Neural mechanism underlyig hyperalgesia response to orofacial pain in Parkinson's disese model rats

2017 Fiscal Year Final Research Report

• Project/Area Number: 26463062
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Surgical dentistry
• Research Institution: Osaka University
• Principal Investigator: Niwa Hitoshi 大阪大学, 歯学研究科, 教授 (30218250)
• Co-Investigator(Kenkyū-buntansha): 前川 博治 大阪大学, 歯学部附属病院, 医員 (10711012) ; 杉村 光隆 大阪大学, 歯学研究科, 准教授 (90244954) ; 浜田 尚香 大阪大学, 歯学部附属病院, 医員 (70762558)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: Parkinson's disease / orofacial pain / formalin test / pain related behavior

Outline of Final Research Achievements

The effect of Parkinson's disease (PD) on pain sensation in the oral facial area was examined using PD model rats, which were produced by the unilateral injection of 6-OHDA into the medial forebrain bundle. PD model rats were injected with 0.05 mL of 4% formalin into the upper lip. The expression of c-Fos in trigeminal spinal nucleus caudalis (Vc), hypothalamic paraventricular nucleus (PVN), parabrachial nucleus (PBN), periaqueductal gray (PAG), nucleus locus ceruleus (LC), and nucleus raphe magnus (NRM) were explored.
As a result, the number of c-Fos positive cells was significantly smaller in the large cell group in PVN than in the control group. The PVN is an important source of brain oxytocin. The depletion of dopamine may cause the change of the activity of the PVN, which may have influenced the analgesic effects mediated by oxytocin.

Free Research Field

orofacial pain