中文摘要：

目的：探讨第一磨牙升高咬合造成的咬合创伤能否引起脑桥结合臂旁核和蓝斑小胶质细胞反应。方法：56只SD大鼠随机分为1h、2h、4h、8h、24h、72h实验组和对照组（n=8），用正畸方丝将上颌第一磨牙咬合升高大约1mm。免疫组化检测OX42阳性小胶质细胞在脑桥臂旁核和蓝斑核的分布和表达变化。结果：正常大鼠的脑桥臂旁核和蓝斑核只有少量弱表达，小胶质细胞处于静息期。在4h和8h，OX42阳性反应增强，小胶质细胞出现轻度反应，在24h达到高峰，小胶质细胞出现明显反应，胞体和分支增粗，细胞突触上小棘样结构明显，72h反应下降。脑桥结合臂旁核外侧反应比内侧强，蓝斑背侧部强于腹侧部。结论：咬台刨伤激活脑桥内蓝斑和结合臂旁核内小胶质细胞，参与伤害性信息传入中枢的处理。

英文摘要：

Objective： To investigate plastic response of the microglias to traumatic occlusion in rat parabrachial nucleus and locus coeruleus. Methods： The occlusal surfaces of the first and second maxillary right molars in 48 SD rats were unilaterally raised by 0,Smm with the square steel, ABC Immunohistochemical method was used to observe the distribution of OX42（a specific marker for microglias）-like immunoreactive（-LI）products in rats brain stem. Results： In normal rats the microglias kept the rested status, OX42 staining was negative or light, cell feature was not clear or could not observed. In experimental rats for 4h, the microglias appeared light response, OX42-L1 was light, OX42-LI cells were found but its feature was not clear. The response ofmicroglias peaked at 24h, OX42-LI became intense, the feature of cells was clear, spines on processes were clearly found. The early reactive microglias were stronger in lateral parabrachial nucleus than medial part, strong in dorsal locus coeruleus than ventral part. In the 72h rats, the response of microglias decreased, OX42-LI became light again. Conclusion： The microglias in parabrachial nucleus and locus coeruleus of bridge of varolius were involved in traumatic occlusion response, from rested state became early activated state. The time course of response was that the response ofmicroglias peaked in rats at 24h, decreased at 8 h and 72h.