情绪应激对大鼠颞颌关节超微结构的影响

目的：观察情绪刺激后大鼠颢颌关节（temporomandibularjoint，TMJ）的电镜表现，研究其超微结构变化。方法：选用优等SD大鼠90只，在模拟情绪应激条件下建立颢下颌关节情绪应激反应动物模型，分别用扫描电镜和透射电镜对连续刺激1周，3周，5周后的大鼠关节盘，髁突及翼外肌纤维进行观察，并与正常组动物进行比较。结果：情绪应激组动物的TMJ出现明显病理性改变，电镜下观察到颢颌关节盘的胶原纤维暴露，髁突关节面表面出现裂隙，其中3周组动物病理性改变最为严重，5周时出现适应性表现。扫描电镜显示1周时髁突深面胶原纤维暴露，裂缝周围纤维排列紊乱。透射电镜可见翼外肌细胞线粒体水肿，嵴减少，基质密度降低，严重者出现空泡样变。结论长期的情绪刺激可能会使TMJ发生病理性改变，但随着情绪刺激时间的延长，关节可能会出现一定程度的修复，这可能与动物的适应性有关。

Study on the influence of emotion stress on ultrastructures of temporomandibular joint in rats

Objective: to study the ultrastructural change of the rat's temporomandibular joints after emotional stimulation. Method: ninety healthy rats were used to found the animal model of the temporomandibular joint reaction to the emotional stimulation. The samples of TMJ discs, condyle and external pterygoid muscle were observed with scanning electron microscope(SEM)and transmission electron microscope(TEM) at 1, 3 and 5 weeks during the emotional stimulation and then compared to the control. Result: the apparent pathological changes could be found in the TMJ of the animals with the emotional stimulations, especially at 3 weeks. The collagen fibers in the TMJ were exposed and some fissures could be observed on the condylar surface under the scanning electron microscope. However, the TMJ pathology started to be partly recovered at 5 weeks, indicating the adaptation of the joint. The external pterygoid muscular cells were shown degenerative signs, such as the edema of mitochondria, reduction of mitochondrial crest and matrix density, or vacuolation in few severe samples. Conclusion: the emotional stimulation could lead to the pathological change of TMJ, but the TMJ could be partly recovered with the elongation of stimulation period, possibly related to the animal's adaptation mechanism.