较低强度两种频率次声波预防雄性去势大鼠骨质疏松的实验研究

100 dB infrasound for the prevention of osteoporosis

目的观察较低强度的两种频率次声波作用于雄性去势大鼠后的股骨骨质变化情况。方法将32只3月龄SD雄性大鼠随机分为正常组(A组)、去势组(B组)、去势后4 Hz次声波作用组(C组)和去势后20 Hz次声波作用组(D组),大鼠行双侧睾丸切除术(A组行假手术)。各组大鼠术后用次声波作用,其中A、B组无次声波输出,C、D组次声波参数分别为4 Hz、100 dB和20 Hz、100 dB,每组每天作用30 min,每周5 d,连续作用12周后处死。用放射免疫法测定血清骨钙素(OCN)浓度;用DPX-IQ型骨密度仪测定左股骨远端骨密度(BMD);取右侧股骨远端制作脱钙石蜡切片,测定骨小梁面积百分比(Tb·Ar)、骨小梁宽度(Th·Th)、骨小梁间隙(Tb·Sp)以及骨小梁数目(Tb·N);取右股骨近端制备硬骨切片,计算骨膜矿化沉积率(MAR)。采用SPSS 10.0统计软件进行Multivariate ANOVA test分析。结果雄性去势大鼠的血清BGP降低,MAR减少,骨小梁宽度和条数、骨小梁百分比减少,骨小梁间隙增加(P<0.05);4 Hz低强度的次声波作用,显著增加了MAR和骨小梁宽度、条数等形态学指标(P<0.05),血清BGP也有增加趋势;20 Hz作用组仅骨小梁宽度和骨小梁数目较去势组改善(P<0.05),余各项指标无显著变化;各组股骨远端BMD无显著变化。结论4 Hz、100 dB的次声波每天作用30 min,可改善雄性去势大鼠的骨质疏松程度。

Objective： To observe the preventive effects of low intensity infrasound on bone loss in orchiectomized rats. Methods： Thirty-two male Sprague Dawley rats were divided into 4 groups （group A-the control group, group B-the osteoporosis group, group C-the 4 Hz infrasound group and group D-the 20 Hz infrasound group）. The rats in groups B, C and D were orchiectomized. Groups C and D were exposed to 4 Hz and 20 Hz infrasound at 100 db, respectively, for 30 min daily, 5 days a week, while groups A and B were not subjected to infrasound exposure. After 12 weeks of infrasound exposure, any changes in serum osteocalcin （OCN）, bone mineral density （BMD） , and such histomorphometric parameters as trabecular area and trabecular thickness, space and number were measured. The mineralization rate （MAR） of the distal femur was measured using image analysis. Results： In group B the MAR was obviously decreased, and the histomorphometric dimensions of the distal femur were less than in group A. There was significantly increased MAR, trabeeular area, trabecular thickness, adifference from group B. In group D, only increases innd trabecular number in group C compared with group B. In group C, serum osteocalcin was also increased, but there was no significant trabecular thickness and trabecular number were observed ; the other measurements had no significant differences from those of group B. There were no significant changes in BMD in groups B, C and D. Conclusion： Exposure to 4 Hz/100 dB infrasound for 30 min a day can prevent bone loss in orchiectomized rats, as demonstrated by significantly increased MAR and trabecular area, thickness and number.