不同去势时间对大鼠牙槽骨微结构影响的比较研究

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

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。

Objective To study the effect of different castrationtime on the microarcbitecture 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 opera- tions. At 3 or 4 months post-surgery, rats in Shamland 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-resistantacid 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 Shaml 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 ovari- ectomy 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 ovari- ectomy may provide a theoretical basis for a suitable animal model of maxillary alveolar bone osteoporosis.