咬合创伤下大鼠三叉神经脊束核尾侧亚核星形胶质细胞的反应及其与细胞因子的关系

Response of astrocytes to occlusal trauma in rat spinal trigeminal nucleus caudalis and its relationship between cytokines

目的:观察咬合创伤时大鼠三叉神经脊束核尾侧亚核(Sp5C)中胶质原纤维酸性蛋白(GFAP)及白介素1(IL-1)、肿瘤坏死因子(TNFα)、一氧化氮合酶(nNOS)mRNA的表达变化,探讨星形胶质细胞及细胞因子在咬合创伤中的作用。方法:将大鼠左侧第一磨牙咬合抬高0.5mm,造成对颌牙的创伤。粘固后1、3、7、14、30d时取三叉神经脊束核尾侧亚核,用反转录-聚合酶链式反应(RT-PCR)检测Sp5C中GFAP,IL-1,TNFα,nNOSmRNA的表达变化。结果:(1)创伤后1dGFAP,IL-1,TNFαmRNA表达即上调,3d时达到峰值,三者呈现相关性一致变化规律,以后虽有下调,仍高于对照组。(2)nNOSmRNA创伤后1d表达上调,14d时达峰值。结论:咬合创伤能导致Sp5C中GFAP,IL-1,TNFα,nNOSmRNA表达上调,且GFAP,IL-1,TNFαmRNA呈现一致性相关变化规律,提示星形胶质细胞及细胞因子参与了咬合创伤的调节过程。

Objective： To investigate the possible role of astrocytes and cytokines on occlusul trauma, detect the expression changes ofGFAP, IL-1 ,TNFα and nNOS mRNA in rat spinal trigeminal nucleus caudalis （Sp5C）. Methods： The occlusal surface of the left first maxillary molars were raised 0.5mm with the square steel. On 1,3,7,14 and 30d after teeth operation, Sp5C were removed.The expression of GFAP mRNA, IL-1 mRNA and TNFα mRNA were detected in both experimental and control groups with reverse transcription-polymerasa chain reaction（RT-PCR）. Results： （1） Comparing to the control group, the gene expression of the GFAP, IL-1, TNFα , nNos mRNA were up-regulated at 1 day and reached peak level at 3 day. （2）The expression of nNos mRNA was significantly up-regulated at 14 day and returned to control level at 4 week. Conclusion： The present results observed the up-regulated expression of GFAP, IL-1 and TNFα mRNA in rat Sp5C after traumatic occlusion and suggested involvement of astrocytes and cytokines in the orofacial pain induced by occlusal trauma.