摘要
目的探讨辐照和微重力对于骨代谢是否存在交互作用。方法 2月龄雄性Wistar大鼠分为正常对照组、X射线辐照组(X-ray组)、尾吊模型组(HLS组)及尾吊结合X射线辐照组(HLS+Xray组)。分别对HLS组和HLS+X-ray组进行4 Gy X射线全身辐照,对HLS+X-ray组进行尾吊实验来模拟空间环境下辐射和微重力的条件,检测骨密度、骨小梁的数目、骨小梁的分离程度、骨小梁的厚度、骨体积分数、结构模型指数等参数并检测了骨碱性磷酸酶(ALP)、酒石酸酸性磷酸酶(TRAP)、骨钙素(OCN)的及骨调节基因Rankl、Runx2、Nfatcl的表达变化,研究两种因素所引起的骨丢失是否有相应的交互作用。结果尾吊和X射线辐照在骨丢失方面引起了显著的变化,同正常对照组相比,HLS组和X-ray组的骨密度、骨小梁的数目、骨小梁的厚度、骨体积分数均表现为降低趋势(P<0.05),HE染色显示HLS组、X-ray组和HLS+X-ray组中都出现骨小梁数量减少等特征,说明各个模型组都存在骨丢失现象,以HLS+X-ray组最为明显(P<0.05)。Rankl、Nfatcl以及酒石酸酸性磷酸酶的表达在HLS组、Xray组及HLS+X-ray组均上升(P<0.05)。碱性怜酸酶和骨钙素的表达在HLS组、X-ray组及HLS+Xray组均有所下降(P<0.05)。而作为成骨细胞特异性表达的Runx2基因在HLS组和X-ray组却没有任何改变,在HLS+X-rays组发生了显著的下调(P<0.05)。结论尾吊和X射线双因素能够引起骨密度更大的丢失,两者存在交互作用,破坏程度会更加严重。
Objective To determine the effect of X-ray radiation and microgravity on bone metabolism. Methods Male Wistar rats were divided into a control group,an X-ray radiation group( X-ray group),a hindlimb suspension group( HLS group),and a hindlimb suspension and X-ray radiation group( HLS + X-ray group). The X-ray radiation dose was 4 Gy,and the hindlimb suspension was adopted to simulate microgravity environment. The bone mineral density,trabecular number,trabecular separation,trabecular thickness,bone volume / trabecular volume,and structural model index were detected,and the changes of bone alkaline phosphatase( ALP),tartrate-resistant acid phosphatase( TRAP),osteocalcin( OCN),and bone regulatory genes( Rankl,Runx2 and Nfatcl) were analyzed. Results The hindlimb suspension and X-ray radiation caused significant reduction( P 〈 0. 05) in bone mineral density,trabecular number,trabecular thickness,and bone volume / trabecular volume in the HLS group,X-ray group and HLS +X-ray group. The bone loss was the most severe in the HLS + X-ray group( P 〈 0. 05). The expression of Rankl,Nfatcl and TRAP were significantly increased( P 〈 0. 05) in the HLS group,X-ray group and HLS +X-ray group,while the expression of ALP and OCN was significantly decreased( P 〈 0. 05). Moreover,Runx2 was not changed in the HLS group and X-ray group,but was down-regulated in the HLS + X-ray group( P 〈 0. 05). Conclusion The combination of hindlimb suspension and X-ray radiation can more severe bone loss than alone.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2015年第12期1232-1236,共5页
Journal of Third Military Medical University
基金
云南省科技厅支持项目(2010BC006)~~