建（牙合）前后SD大鼠髁突软骨中DMP1表达变化的实验研究

发布时间：2018-06-23 05:33

本文选题：建(?) + 髁突　；参考：《昆明医科大学》2017年硕士论文

【摘要】：[目的]建立不同周龄SD大鼠动物模型,观察大鼠建(?)前后颞下颌关节髁状突的发育改建情况以及髁突软骨中DMP1的表达规律,探讨咀嚼力变化对髁突的影响。[方法]实验一选取新生(0)、3、5、6、8周龄雄性SD大鼠各6只,取右侧髁状突组织,HE染色观察大鼠髁突发育过程中的软骨厚度、软骨下骨BV/TV、Tb.Th、Tb.N以及Tb.Sp的变化特征,免疫组化染色检测髁突软骨中DMP1的表达情况。实验二选取5周龄雄性SD大鼠共36只,随机分配至软食组以及正常组各18只,适应性喂养一周后开始建模,予软食组大鼠喂粉末状饲料,正常组大鼠喂普通棒状饲料,其他饲养条件不变。分别于建模后2、4、6周处死大鼠,HE染色观察大鼠髁突软骨厚度、软骨下骨BV/TV、Tb.Th、Tb.N以及Tb.Sp的变化,免疫组化染色检测各组大鼠髁突软骨中DMP1的表达情况。采用Image Pro Plus 6.0图像分析系统进行组织学测量分析,结果应用SPSS 23.0统计分析软件进行统计分析。[结果]1.实验一:大鼠髁突软骨组织学厚度在0-8周龄期间降低,其中3-8周龄软骨厚度显著降低(P0.05),以增殖层逐渐增厚(P0.05),成软骨细胞层逐渐变薄为特征(P0.05);软骨下骨:随大鼠周龄的增长,BV/TV、Tb.Th均明显增加(P0.05),而Tb.N呈下降趋势(P0.05),Tb.Sp:8w组较3w组虽稍有增加,但差异无统计学意义(P0.05);DMP1:主要表达于髁突软骨成软骨细胞层和肥大层的细胞内;大鼠0-8周龄期间,成软骨细胞层中DMP1的表达量呈逐渐降低的趋势(P0.05);而肥大层中其表达量却逐渐升高(P0.05)。2.实验二:各个时间点,软食组分别与正常组比较,软食组髁突软骨厚度明显下降(P.0.05);软食组软骨下骨BV/TV和Tb.Th呈现显著性下降的态势(P0.05),Tb.N却呈上升态势(P0.05);Tb.Sp各组间比较,差异无统计学意义(P0.05)。DMP1:在8w、10w时,软食组DMP1表达量均显著低于正常组(P0.05);12w时,软食组DMP1表达量虽稍低于正常组,但差异无统计学意义(P0.05)。[结论]1.髁突的发育呈周期性变化。3周龄大鼠(离乳后)髁突软骨的生长发育加速,以软骨厚度降低、软骨增殖层厚度增加为特征。6周龄大鼠(建(?)后)软骨下骨骨化速度加快,以BV/TV、Tb.Th大幅度增加以及Th.N显著性降低为特征。证明咀嚼应力的刺激对髁突的生长发育很有必要。2.软食喂养没有导致大鼠体重降低,但其引起的咀嚼力变化可导致髁突骨组织发生退行性改建,以髁突软骨厚度及软骨下骨BV/TV、Tb.Th均降低为特征。进一步证实正常咀嚼力刺激对于髁突软骨及软骨下骨组织形态维持至关重要。3.DMP1主要表达于髁突软骨成软骨细胞层和肥大层的细胞内,揭示其在髁突软骨生长发育中发挥重要作用。软食喂养引起的咀嚼力变化,可导致髁突软骨中DMP1的表达量较正常组显著降低,推测DMP1可能参与髁突软骨改建过程中的生物力学信号传导通路。
[Abstract]:[objective] to establish SD rat models of different weeks of age and observe the establishment of SD rats. The development and remodeling of the condyle of anterior and posterior temporomandibular joint and the expression of DMP1 in condylar cartilage were studied to investigate the effect of the change of masticatory force on the condyle. [methods] in experiment one, 6 male Sprague-Dawley rats aged 8 weeks (0) were selected. The right condylar tissue was stained with HE to observe the thickness of cartilage, the changes of TVB / Tb. Thb.N and Tb.Sp in the subchondral bone of rats during the development of condyle. The expression of DMP1 in condylar cartilage was detected by immunohistochemical staining. In experiment 2, 36 male SD rats aged 5 weeks were randomly assigned to the soft food group and the normal group, 18 rats in each group. After one week of adaptive feeding, the rats in the soft food group were fed with powder feed and the normal group rats were fed with ordinary rod feed. Other feeding conditions remain unchanged. The thickness of condylar cartilage, the changes of subchondral BV / TVT Tb. Tb.N and Tb.Sp were observed by HE staining. The expression of DMP1 in condylar cartilage of rats in each group was detected by immunohistochemical staining. The image Pro Plus 6.0 image analysis system was used for histologic measurement and analysis. The results were analyzed by SPSS 23.0 statistical analysis software. [result] 1. Experiment 1: the histological thickness of condylar cartilage in rats decreased during 0-8 weeks of age. The thickness of cartilage at 3-8 weeks was significantly decreased (P0.05), characterized by the gradual thickening of proliferative layer (P0.05) and the gradual thinning of chondroblast layer (P0.05); the subchondral bone: BV / TVTVTb 路Th significantly increased with the increase of age (P0.05), while Tb.N showed a decreasing trend (P0.05). But the difference was not statistically significant (P0.05): DMP1 was mainly expressed in the chondroblast layer and hypertrophic layer of condylar chondrocytes. The expression of DMP1 in chondroblast layer decreased gradually (P0.05), but increased in hypertrophic layer (P0.05). Experiment 2: at each time point, the thickness of condylar cartilage in soft food group was significantly lower than that in normal group (P.0.05), while BV / TV and Tb 路Th in soft food group were significantly decreased (P0.05), but Tb.N was increased (P0.05). There was no significant difference (P0.05). DMP1 expression in soft food group was significantly lower than that in normal group (P0.05) 12 weeks after 8 weeks (P0.05), but there was no significant difference in DMP1 expression in soft food group (P0.05). [conclusion] 1. The development of condyle showed periodic changes. The growth and development of condylar cartilage was accelerated in 3 weeks old rats (postlactation). The thickness of cartilage decreased and the thickness of proliferative layer of cartilage increased. The ossification of the subchondral bone was accelerated, characterized by the significant increase of Tb.Th and the decrease of Th.N. It is proved that the stimulation of masticatory stress is necessary for the growth and development of condyle. Soft feeding did not result in weight loss, but the change of masticatory power caused by soft feeding could result in degenerative remodeling of condylar bone tissue, which was characterized by the reduction of condylar cartilage thickness and the decrease of BV / TVV Tb.Th in subchondral bone. It was further confirmed that normal masticatory stimulation was essential to the morphological maintenance of condylar cartilage and subchondral bone. 3. DMP1 was mainly expressed in the chondroblast layer and hypertrophic layer of condylar cartilage. It is revealed that it plays an important role in the growth and development of condylar cartilage. The change of masticatory power induced by soft food feeding resulted in a significant decrease in the expression of DMP1 in condylar cartilage, which suggested that DMP1 might be involved in biomechanical signal transduction pathway during condylar cartilage remodeling.
【学位授予单位】：昆明医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R782.6

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