Marchetti C, Cornaglia I, Casasco A, Bernasconi G, Baciliero U, Stetler-Stevenson W G
Istituto di Istologia ed Embriologia Generale, University Pavia, Italy.
Arch Oral Biol. 1999 Apr;44(4):297-304. doi: 10.1016/s0003-9969(98)00107-1.
The fibrous tissue of the articular disc of the dysfunctional temporomandibular joint undergoes deep and variable structural modifications. Here the concurrence of morphological changes and the expression of matrix metalloproteinase-2 (MMP-2) in damaged discs from individuals suffering joint dysfunction was investigated. Microscopic, ultrastructural and immunocytochemical investigations were made on variously damaged articular discs and on one control sample. Disaggregation of collagen fibres, an increase in cellular components and calcification of large areas of tissue were observed in the damaged discs. These modifications were accompanied by a positive immunoreaction pattern for MMP-2. Fibroblast-, chondroblast- and osteoblast-like cells displayed a positive cytoplasmic reaction. In samples displaying evidence of synovial hyperplasia, some cells of the synovial protrusions were MMP-2 immunoreactive. No MMP-2 staining was observed in the control sample. These findings demonstrate that structural modifications of the articular disc could be specific responses to changes in the function of the temporomandibular joint. Variations in extrinsic stimuli may activate intrinsic factors, such as MMPs, that induce structural modifications in the discal tissue.
功能失调的颞下颌关节关节盘的纤维组织会经历深度且多样的结构改变。在此，对关节功能失调个体受损关节盘中形态学变化与基质金属蛋白酶-2（MMP-2）表达的同时出现情况进行了研究。对不同程度受损的关节盘以及一个对照样本进行了显微镜、超微结构和免疫细胞化学研究。在受损关节盘中观察到胶原纤维解聚、细胞成分增加以及大面积组织钙化。这些改变伴随着MMP-2的阳性免疫反应模式。成纤维细胞样、成软骨细胞样和成骨细胞样细胞呈现阳性细胞质反应。在显示滑膜增生迹象的样本中，滑膜突起的一些细胞呈MMP-2免疫反应阳性。在对照样本中未观察到MMP-2染色。这些发现表明关节盘的结构改变可能是对颞下颌关节功能变化的特异性反应。外在刺激的变化可能激活内在因素，如基质金属蛋白酶，从而诱导盘状组织的结构改变。
