Expression of tenascin-Xon rat TMJ in functional property

tenascin家族包括tenascin- c、-X、-R和N，是已知的细胞外基质之一。主要观察到关节超伸性韧带和肌腱中检测到的tenascin-X和与细胞粘附和结合有关的tenascin-C。在本研究中，我们研究了大鼠TMJ和咬肌在TMJ形成期和软饲粮中tenascin-C和-X的转录和翻译水平。发育过程中腱素的分布：妊娠第18天，在咬肌、结缔组织、下颌髁和下颌窝骨基质中检测到腱素c和X。妊娠第20天，在TMJ椎间盘上侧检测到tenascin-X，与tenascin-C相比。在产后，tenascin- c主要在咬肌和椎间盘中部检测到，而tenascin- X主要在肌腱连接处、椎间盘中部和外区以及下颌窝骨基质中检测到。这些结果提示，从妊娠20天到产后，tenascin家族的定位发生变化，同时发生细胞运动和粘附，导致TMJ发育。新生儿期Tenascin-C mRNA的表达高于tenascin-X mRNA，但在其他时期两者的表达水平无差异。这表明，在新生儿时期，这两者起着不同的作用。根据对tenascin-C和-X在TMJ椎间盘不同定位的观察，tenascin-C和-X似乎与TMJ椎间盘发育有特殊关系。软性饮食的效果：断奶后，一组喂食软性饮食，另一组喂食正常饮食，为期三周。Tenascin-C主要在两组椎间盘的前后区检测到。软性饮食组在第1周的胃盘中部出现了强烈的反应。两组和软食组均出现Tenascin-X与tenascin-C相同的区域，第1周在椎间盘上侧出现强烈反应。对照组下颌骨髁突软骨及椎间盘内外区均可见pcna阳性细胞。软饲组pcna阳性细胞数在第1周下降，第3周增加。下颌骨窝和髁突骨基质均可见凋亡阳性细胞，软食组和软食组第2周髁突软骨细胞凋亡阳性细胞，第8周软骨细胞和上皮组织凋亡阳性细胞。说明3周软饲应激改变了腱素-C和-X的分布，改变了TMJ组成的细胞和组织，机械应激导致细胞运动和分离。少

The tenascin family including tenascin-C, -X, -R, and N is known as one of extracellular matrix. Mainly tenascin-X, which is detected in ligaments and tendon of the joint hyperextensibility, and tenascin-C, which is associated with cell adhesion and conjugation, are observed. in this study, we investigated the transcription and translation levels of tenascin-C and -X in rat TMJ and masseter muscle during TMJ forming period, and on soft diet.1.Distribution of tenascin during development : Tenascin-C and X were detected in masseter muscle, connective tissue, and the bone matrix in the mandibular condyle and the mandibular fossa, on 18-days gestation. On 20-days gestation, tenascin-X was detected in the upper side of the TMJ disk in contrast to that of tenascin-C. During postnatal period, while tenascin-C was detected on masseter muscle and the middle region of the disk, tenascin X was detected mainly on the myotendinous junction, middle and outer regions of the disk and the bone matrix i … More n the mandibular fossa. These results suggest that in the period from 20-days gestation to postnatal, the localization of the tenascin family changes, at the same time cell movement and adhesion take place, resulting in the developed TMJ. Tenascin-C mRNA expressed more than tenascin-X mRNA in the newborn period, although the expression level of these had no difference in other periods. This suggests that in the newborn period these two play different roles. it seems according to the observation on the different localization of tenascin-C and -X in the TMJ disk that tenascin-C and -X are specially related to TMJ disk development.2.The effect of a soft diet : After weaning, one group was fed on a soft diet, while the other group was fed on a normal diet for three weeks. Tenascin-C was detected mainly on anterior and posterior regions of the disk in both groups. Especially the strong reaction was observed on the middle region of the disk in soft diet group in the first week. Tenascin-X was revealed the same region of tenascin-C in both groups and in soft diet group, the strong reaction was observed on the upper side of the disk in the first week. The PCNA-positive cell was observed on cartilage of mandibular condyle and inner and outer region of the disk in control group. In soft diet group, the number of the PCNA-positive cells decreased in the first week, then increased in the third week. The apoptosis-positive cell was observed on the bone matrix in the mandibular fossa and the mandibular condyle, in both groups in soft diet group the apoptosis-positive cells was also observed on cartilage of the condyle in the second week, and on cartilage cells and epithelial tissues in the eighth week. This suggests that the distribution of tenascin -C and -X, and cells and tissues composed of TMJ were changed by the stress of a soft diet for three weeks, and that mechanical stress causes cell movement and separation. Less