咀嚼负荷对幼兔髁突软骨细胞BrdU标记影响的研究  

Effect of masticatory force on cell proliferation of the condylar cartilage in growing rabbits using Bromodeoxyuridine labeling

作　　者：刘晨燕[1] 冯剑颖[1] 谷志远[2] 

机构地区：[1]浙江中医药大学口腔医学院正畸科,浙江杭州310053 [2]浙江中医药大学口腔医学院口腔颌面外科,浙江杭州310053

出　　处：《口腔医学》2015年第4期250-253,286,共5页Stomatology

基　　金：国家自然科学基金(81200802);浙江省自然科学基金(YZ111273)

摘　　要：目的探讨咀嚼负荷对幼兔髁突软骨发育及软骨细胞中BrdU标记的影响。方法出生10 d龄的32只幼兔,随机分为喂食固体硬饲料组和喂食粉末软饲料组。连续2周每天每只腹腔注射BrdU(50 mg/kg),在2、4、6、8周时每组处死4只幼兔,HE观察组织形态学变化测量软硬组髁突厚度变化,免疫组化检测BrdU表达。结果髁突软骨前部厚度硬食组明显高于软食组,在中部无明显差异,髁突软骨后部厚度软食组高于硬食组。BrdU免疫组化染色显示,发育期髁突软骨各层及软骨下骨骨髓腔内均有BrdU阳性标记,前部的增殖层表达最显著。第2周,硬食组在前、中、后3个部位的BrdU阳性率都高于软食组;第6周,软食组的中、后部位的阳性率高于硬食组;第8周,软硬组均检测不到阳性细胞。结论软食组在低咀嚼力刺激下,幼兔髁突软骨细胞增殖启动较慢。适当的咀嚼压力能促进髁突软骨细胞的增殖,同时幼兔发育期的髁突生长还受到基因等内环境因素影响。Objective To explore the effect of masticatory force on development of condylar cartilage and the BrdU labeling in growing rabbits. Methods Thirty-two,10-day-old New Zealand white rabbits were divided into two groups randomly. One group received the normal hard diet and the other group received a powder soft diet. Both groups were injected intraperitoneally with bromodeoxyuridine（BrdU） 50mg/kg for 2 consecutive weeks and then sacrificed at 2,4,6,8 weeks after the first BrdU injection. Presence of BrdU was detected using immunohistochemistry and morphological change was examined by HE staining. Results Compared with the soft-diet group,the thickness of anterior part of condylar cartilage in the hard-diet group increased significantly. There was no significant change in the thickness of intermediate part of condylar cartilage. The thickness of posterior part of condylar cartilage was thicker in the soft-diet group. Immunohistochemical analysis revealed staining of BrdU localized in the all cartilage zones and subchondral bone. BrdU-positive cells were abundantly detected in the proliferative zone. The BrdU labeling rate of hard-diet group in anterior intermediate and posterior part of condylar cartilage was higher than the soft-diet group significantly in the 2nd week. The BrdU labeling rate of soft-diet group in intermediate and posterior part of condylar cartilage was higher than the hard-diet group significantly in the 6th week. In 8th week BrdUpositive cells couldn＇t be detected in both groups. Conclusions The growing rabbits with low masticatory force have a slow proliferation initiation. It suggests that the proper masticatory force can promote the proliferation of cell in cartilage and the development of condylar is still affected by the internal factor such as gene.

关 键 词：髁突软骨 咀嚼力 BRDU标记 增殖 兔 

分 类 号：R318.01[医药卫生—生物医学工程]