不同去势时间对大鼠牙槽骨微结构影响的比较研究

目的 比较不同去势时间对大鼠牙槽骨微结构的影响，探讨牙槽骨骨质疏松大鼠模型建立成功的参数。方法 24只6月龄雌性SD大鼠，随机分为4组：（1）对照组1（Sham1）；（2）去势组1（OVX1）；（3）对照组2（Sham2）；（4）去势组2（OVX2）。分别在全麻下行假手术和双侧卵巢去势术。于术后3个月和4个月处死各组大鼠，取双侧上颌骨标本，通过Micro-CT扫描、HE染色、抗酒石酸酸性磷酸酶（TRAP）染色、Van Gieson染色、荧光双标观察并分析牙槽骨微结构的变化。结果 去势3个月后OVX1组与Sham1组大鼠相比，体重增加25.09%（P<0.01）；牙槽骨骨体积分数（BV/TV）、骨小梁数目（Tb.N）、骨小梁分离度（Tb.Sp），牙骨质界-牙槽嵴顶（CEJ-ABC）距离无改变（P>0.05），骨小梁宽度（Tb.Th）降低了12.44%（P<0.05），破骨细胞数量增加了40.12%（P<0.01）；骨形成沉积率（MAR）无明显改变（P>0.05）；去势4个月后OVX1组与Sham1组大鼠相比，体重进一步增加了26.25%（P<0.01），BV/TV、Tb.Th、MAR分别降低了11.15%、17.22%和38.45%（P<0.01），Tb.Sp和破骨细胞数量分别增加了81.89%和35.67%（P<0.01），Tb.N和CEJ-ABC距离无变化（P>0.05），HE和Van Gieson染色均表明OVX2组大鼠牙槽骨骨量降低，骨髓腔面积增加，骨小梁微结构破坏、变细，部分区域发生断裂。结论 6月龄雌性SD大鼠去势4个月后，牙槽骨发生明显骨质疏松，可作为合适的牙槽骨骨质疏松大鼠模型参数的理论依据。

A comparative study of the effects of different castrationtime on the microarchitecture of alveolar bone in rats

Objective To study the effect of different castrationtime on the microarchitecture of alveolar bone in rats. Methods Twenty-four 6-month-old female Sprague Dawley rats were randomly assigned to four groups:SHAM1,OVX1,Sham2, and OVX2. Rats were subjected to either bilateral ovariectomy or sham operations. At 3 or 4 months post-surgery, rats in Sham1and OVX1, or Sham2 and OVX2 were sacrificed. Both sides of the maxillae were removed from each rat for alveolar bone microarchitecture examination, including micro-computed (micro-CT) tomography, hematoxylin and eosin (H&E) staining, Van Gieson''s staining, tartrate-resistant acid phosphatase (TRAP) staining, and sequential fluorescent labeling. Results 3 months after surgery, there was no significant difference in the alveolar bone mass between OVX1 group and Sham1 group in BV/TV, Tb.N,Tb.Sp, CEJ-ABC, or MAR (P>0.05). When compared with sham1 rats, Tb.Th decreased (12.44%, P<0.05) and the number of osteoclasts increased (40.12%, P<0.01)in OVX1 rats. 4 months after surgery, BV/TV, Tb.Th and MAR were significantly reduced (11.15%, 17.22%, and 38.45%, respectively), while Tb.Sp and the number of osteoclasts were significantly increased (81.89%, and 35.67%, respectively), in the OVX2 group compared to the Sham2 group (P<0.01). Van Gieson''s and H&E staining of maxilla showed that the trabecular bone was affected by the ovariectomy operation after 4 months, with Sham2 group having increased bone marrow volume compared with OVX2 group. Conclusions The 6-month-old female Sprague-Dawley rat with a 4-months observation period after ovariectomy may provide a theoretical basis for a suitable animal model of maxillary alveolar bone osteoporosis.