The effect on the temporomandibular joint morphogenesis and its development by restriction of jaw movement in mice

通过上颌-下颌固定，未发现明显的全身发育迟缓胚胎。但在口腔运动受限的颞下颌部，髁头软骨与颈部钙化骨之间的边界在宏观上变得不清晰和弥散。髁突头软骨膜细胞变形、排列紊乱，增生带与肥大前带之间存在异常骨化现象，细胞排列不连续。这一发现提示下颚运动在产前颞下颌关节发育中起重要作用。碱性成纤维细胞生长因子（b-FGF）及其受体（FGFR-3）的免疫组化染色和western blotting方法显示，在胚胎日（e15.5和E17.5），在髁浅软骨细胞中，而在更深的增殖区和增厚前区，具有高染色性。而在成年男女中，b-FGF和FGFR-3在软骨细胞浅层区表现出较高的染色性，并逐渐向深层区下降。这些分子似乎在钙化机制中起作用。对正常生长的FGFR-3进行Western blotting分析，在15.5、17.5和第11天出生时显示出较高的可染色性，但在成人中显示出较弱的可染色性。B-FGF在对照组中也有类似的趋势，但在成人中几乎没有染色。

By the maxillo-mandibular fixation, no significant systemic growth retardation of the embryo was not detected. But at the temporomandibular portion of the mouth movement restriction, the border between the cartilage of the condylar head and the calcified bone in the neck became unclear and diffuse macroscopically.Deformed and disarranged cells were found in fee perichondrium of the condylar head, furthermore abnormal ossification was also observed between the proliferating and prehypertrophic zones and therefore discontinuity cell arrangement was characteristic. This finding suggested that jaw movement played an important role in the prenatal development of the temporomandibular joint. From the immunohistochemical staining and western blotting method of basic fibroblast growth factor (b-FGF) and its receptor (FGFR-3) revealed high stainability not in the superficial condylar chondrocytes but rather deeper proliferating and prehypertrophic zones at the embryonic day (E) 15.5, and E17.5. While in adults of both sex, b-FGF and FGFR-3 showed a high stainability in the superficial chondrocyte zone and gradually decreased towards to deeper zones. These molecules seemed to function in the mechanisms of calcification. Western blotting analysis of FGFR-3 in the normal growth showed a high stainability at the E 15.5, E 17.5 and at 11th day birth but in adult it revealed a weak stainability. B-FGF in the control group revealed a similar tendency but in adult at most little staining was observed.