脉冲电磁场预防骨质疏松模型的实验研究

为检验脉冲电磁场对去卵巢大鼠骨质疏松模型的预防效果,用30只质量180-220 g 3月龄雌性未孕SD大鼠去势建立骨质疏松模型,并随机分成正常对照组(SHAM)、去势对照组(OVX)、脉冲电磁场(PEMFs)组,每组10只,其中SHAM组作假手术,不切除卵巢,其余2组做双侧卵巢切除术;PEMFs组选用15 Hz脉冲电磁场,2 h/d,1次/d;SHAM组和OVX组不予任何处理,分别作为阳、阴性对照组,并用双能X射线骨密度仪检测腰椎和股骨骨密度。实验结果表明,脉冲电磁场照射后,校正骨密度低于正常对照组;与OVX组相比,脉冲电磁场照射后去势大鼠椎骨校正骨密度(16周时,P<0.001和24周时P<0.01)和股骨校正骨密度(16周时P<0.001和24周时P<0.01)提高,脉冲电磁场能改善去势大鼠骨质疏松具有预防作用,对脉冲电磁场应用于人体骨质疏松相关疾病的防治具有现实意义。

Preventive Effects of Pulsed Electromagnetic Fields on Osteoporosis Model Induced by Ovariectomy

To investigate the preventive effects of pulsed electromagnetic fields(PEMFs) with specific parameters on osteoporosis,thirty 3-month old female Sprague-Dawley rats were randomly divided into three different groups: normal control group(SHAM group),ovariectomized control group(OVX group),pulsed electromagnetic fields exposing group(PEMFs group),each group had 10 rats.Rats in the SHAM group received the dorsal switch operation,and the other two groups were ovariectomized bilaterally;PEMFs group were exposed to pulsed electromagenetic fields with frequency 15 Hz,peak magnetic induction density 2.2mT and exposure time 2 hours per day,OVX and SHAM group served as control groups. Bone mineral density(BMD) of vertebra and left femur were measured using dual energy X-ray absorptiometry(NORLAND DXA-X36) after surgery.In the experimental period,the corrected vertebral BMD of PEMFs group is significantly higher than that of OVX group separately(P<0.001 at 16 weeks,P<0.01 at 24 weeks).The corrected femoral BMD of PEMFs groups is significantly different form that of OVX group(P<0.001 at 16weeks,P<0.01 at 24weeks).The corrected BMD of PEMFs is still lower than those of SHAM groups.Experimental results indicate that extremely low frequency pulsed electromagnetic fields slowed down the speed of corrected vertebral and femoral BMD loss in ovariectomized rats and verify the preventive effects on osteoporosis rats induced by bilateral ovariectomy.Consequently,we conclude that PEMFs exposure,a noninvasive treatment,would be beneficial to the osteoposotic diseases.