Pulp Biology and Endodontics, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
J Endod. 2010 Mar;36(3):459-64. doi: 10.1016/j.joen.2009.12.011.
Bacterial infection and resulting inflammation of the dental pulp might not only trigger neuroimmune interactions in this tissue but also sensitize the central nervous system (CNS) such as the thalamus via nociceptive neurons. Thus, immunopathologic changes in the rat thalamus that take place after pulp inflammation were investigated.
Pulp exposure was made in mandibular right first molars of 5-week-old Wistar rats. After 24 hours, the thalamus was retrieved and subjected to either immunohistochemistry for class II major histocompatibility complex (MHC) molecules and glial fibrillary acidic protein (GFAP) or mRNA expression analysis of antigen-presenting cell-related molecules and N-methyl-D-aspartate receptor 2D subunit (NR2D) by means of reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR.
At 24 hours after pulp exposure, the density of class II MHC molecule-expressing and GFAP-expressing cells was increased in the contralateral thalamus. Gene expression analysis revealed the up-regulation of class II MHC molecules, CD80, CD83, CD86, and NR2D in the contralateral thalamus, as compared with the ipsilateral thalamus.
These results suggest the signal of pulp inflammation induces neuronal activation in the CNS.
细菌感染和由此引起的牙髓炎症不仅可能触发该组织中的神经免疫相互作用,还可能通过伤害性神经元使中枢神经系统(CNS)如丘脑致敏。因此,研究了牙髓炎症后大鼠丘脑发生的免疫病理变化。
在 5 周龄 Wistar 大鼠的下颌右侧第一磨牙中进行牙髓暴露。24 小时后,取出丘脑并进行 II 类主要组织相容性复合体(MHC)分子和神经胶质纤维酸性蛋白(GFAP)的免疫组织化学染色,或通过逆转录-聚合酶链反应(RT-PCR)和实时 PCR 分析抗原呈递细胞相关分子和 N-甲基-D-天冬氨酸受体 2D 亚基(NR2D)的 mRNA 表达。
牙髓暴露后 24 小时,对侧丘脑 II 类 MHC 分子表达细胞和 GFAP 表达细胞的密度增加。基因表达分析显示,与同侧丘脑相比,对侧丘脑 II 类 MHC 分子、CD80、CD83、CD86 和 NR2D 的表达上调。
这些结果表明,牙髓炎症的信号诱导中枢神经系统中的神经元激活。