应激原去除后大鼠颞下颌关节超微结构的变化

目的 观察大鼠在应激原去除后颞下颌关节髁突、关节盘超微结构的变化.方法 12周雄性Wistar大鼠32只,按完全随机设计分为实验组和对照组,各组16只,各组又随机分为9周组和12周组,各为8只大鼠.实验组前6周建立慢性不可预知性应激模型(chronic unpredictable stress,CUS),然后去除各种刺激因素,改为正常饲养;对照组始终正常饮食,不加任何刺激.9周、12周时间点分别处死9周组和12周组大鼠,完整分离大鼠左侧髁突和关节盘,制作电镜标本,扫描电镜下观察大鼠髁突及关节盘下腔面超微结构的变化.结果 实验组大鼠髁突及关节盘下腔面扫描电镜下出现不同程度的恢复情况,表现为胶原纤维排列变得有规律,深层暴露减少,表面凝胶样物质增多等,对照组大鼠无明显变化.结论 应激造成的大鼠颞下颌关节局部的病理损伤变化在一定时间内是可以恢复的,即该病理过程是可逆的.

Chnnges of the ultrastructures of temporomandibular joint after removal of emotional stress factors in rats

Objective To examine the changes of the ultragtructures of temporomandibular joint after removal of the emotional stress factors in rats.Methods Thirty-two 12-week-old male Wistar rats were divided into two groups randomly,experimental group and control group.Each group was divided into two subgroups according to execution time,9-week subgroup and 12-week subgroup with eight rats in each subgroup.Chronic unpredictable stress animal model were firstly established in experimental group in the first 6 weeks,then all the stimulation factors removed and breed normally.After 9 weeks,rats in 9-week subgroup were killed.After 12 weeks,rats in 12-week subgroup were killed.All condyles and articular discs were dissected and observed by scanning electron microscope. Results There wag some recovery in condyles and articular discs in experimental group under scanning electron microscope.The gelatum on the surface of condyles increased,collagen fibrils became regular and deep layer collagen fibrils less exposed.There were no such obvious changes on the surface of condyles and articular discs in control group.Conclusions The ultrastructure injures of temporomandibular joint in rats induced by emotional stress could be reversed if the stress factors were removed.