【摘要】 目的 :初探正常咬合力下大鼠牙周膜Ⅰ型胶原在分子水平的改建情况。方法 :选用雄性Wistar大鼠 ,采用地高辛标记寡核苷酸探针原位杂交法 ,检测大鼠牙周膜Ⅰ型胶原mRNA的表达情况。结果 :大鼠磨牙牙周膜有很强的Ⅰ型胶原信号 ,分布基本均匀 ,但仍具有一定的空间特异性 :近中侧牙槽骨骨壁上有较多致密信号 ,而远中侧无信号。结论 :牙周膜Ⅰ型胶原mRNA的表达与咬合力密切相关。更多还原

【Abstract】 Objective:The main component of the periodontal ligament(PDL) is collagen fiber, especially typeⅠcollagen, and collagen plays an important role in PDL. The aim of this study is to observe the expression of rat PDL mRNA under normal bite force and to investigate the molecular mechanisms of these changes in type Ⅰ collagen mRNA.Methods: 40 male Wistar rats were used, and animals were intra_cardiac perfused with a solution of 4% polyformaldehyde under anesthesia. Dissected mandibles were immersed in the same fixation for 6 hours and subsequently decalcified in EDTA. The demineralized specimens were embedded in paraffin and cut into slices with thickness 5 μm. The probe was synthesized and labeled with digoxigenin. Expression of typeⅠcollagen mRNA was measured by using in situ hybridization(ISH).Results: Under the normal bite force , the mRNA expression of typeⅠ collagen was very strong on the whole, including the alveolar bone side, the root side and the area between them. Positive signals were located mainly in the cytoplasm and some in the nuclei. But the mRNA expression of typeⅠ collagen still had spatial characteristics. The signals in some fibroblasts were apparently stronger than those in other fibroblasts in the apical 1/3 fragment of the roots. The signal of typeⅠ collagen mRNA was strong near the root sides. The expression signal on the proximal alveolar walls was strong,however, on the distal alveolar wall, there was no expression.Conclusion: The expression of typeⅠcollagen mRNA is closely related with bite force.更多还原