软骨细胞增殖与凋亡在人重组白细胞介素-1β介导的颞下颌关节炎症损伤中的意义

Roles of Proliferation and Apoptosis of Chondrocytes in Inflammatory Lesions Mediated by Recombinant Human Interleukin-1β on Condylar Cartilage of Temporomandibular Joint

目的 :探讨细胞增殖与凋亡在人重组白细胞介素_1β介导的颞颌关节炎症损伤中的作用。 方法 :选用SD大鼠颞下颌关节腔内反复多次注射rhIL_1β ,造成炎症损伤 ,利用免疫组织化学染色及原位末端标记法 ,观察炎症损伤过程中髁突软骨细胞增殖及凋亡的变化。结果 :注射后 1～ 30d ,实验侧髁突软骨增殖层PCNA阳性指数均较对照侧低 ,以 1～ 7d最明显 ;实验侧髁突软骨细胞凋亡数较对照侧多 ,主要分布于软骨增殖层及前肥厚层中 ,以 1～ 7d最明显 ,15d后凋亡细胞数明显减少 ,仅见个别凋亡细胞散在分布于软骨浅层。结论 :rhIL_1β关节内注射不仅使髁突软骨细胞增殖受抑制 ,而且细胞凋亡也可能是rhIL_1β致关节损伤的途径之一 。

Objective:The purpose of this study was to evaluate the role of cell proliferation and apoptosis in the inflammatory lesion mediated by recombinant human interleukin_1β on condylar cartilage of temporomandibular joint. Methods:The model of inflammatory lesion of temporomandibular joint in SD rats was established by intraarticular injection with recombinant human interleukin_1β. The expressions of proliferating cell nuclear antigen (PCNA) and apoptosis in cartilage were examined by immunohistochemical staining and Tdt_mediated dUTP nick end labelling (TUNEL) during series time of after injection of recombinant human interleukin_1β. Results:The immunostaiing results showed that PCNA protein was expressed in proliferative zone of condylar cartilage, the positive index of PCNA decreased in proliferative zone after injection of recombinant human interleukin_1β1～30 days, and more obviously in 1～7 days. Apoptotic chondrocytes were mainly located in proliferative zone and the prehypertrophic zones, and the apoptotic chondrocytes increased in proliferative and prehypertrophic zones of condylar cartilage (P<0 05). Conclusion:These results suggest that suppression of proliferating cell nuclear antigen and high apoptosis of chondrocytes may play an important role in the inflammatory lesion or in the destructive process of temporomandibular joint osteoarthritis. \;