正弦交变电磁场促进体外培养成骨细胞成熟矿化的时间效应

Time Effect of Sinusoidal Electromagnetic Field on Enhancing the Maturation and Mineralization of Osteoblasts in Vitro

研究正弦交变电磁场(SEMFs)促进体外培养成骨细胞(OB)成熟矿化的时间效应。OB培养后随机分成7组,其中6组用50Hz、1.8mT SEMFs处理,处理时间为每天0.5、1.0、1.5、2.0、2.5和3.0h,1组0h(对照组)。倒置相差显微镜下观察各组细胞形态;48h后检测细胞增殖情况;第3、6、9、12d测定碱性磷酸酶(ALP)活性,第10d茜素红钙化结节染色。磁场处理8d后形成漩涡样分布的钙化节结;各磁场处理组均抑制细胞增殖;ALP活性从0.5～1.5h依次递增,从1.5～3.0h依次递减,1.5h组的ALP活性始终高于对照组(P<0.05),第9d时显著高于其他各磁场处理组(P<0.05);茜素红染色结果显示,1.0、1.5和2.0h组的钙化结节数明显多于对照组。50Hz、1.8mT SEMFs抑制体外培养OB的增殖,但对其分化成熟和矿化过程有显著促进作用,此作用与磁场处理时间有关,尤以1.5h促分化效果最为明显。

The present research was to investigate the time effect of sinusoidal electromagnetic fields（SEMFs）at different exposure time on the proliferation and differentiation of osteoblasts （OB） in vitro. The newborn rat calvarial OB were isolated by enzyme digestion and divided randomly into 7 groups after one passage. The exposure times of the SEMFs were 0.5h, 1.0h, 1.5h, 2. Oh, 2.5h and 3.0h, respectively, and the frequency was 50Hz. The cells were exposed in the SEMFs of 1.8mT. Those without SEMFs exposure were used as the control group. They were observed under the contrast phase microscope each day. After 48h, cell proliferation was assayed by MTT method. The alkaline phosphatase （Alkaline Phosphatase, ALP） activities were measured after the exposure of SEMFs for 3d, 6d, 9d and 12d, respectively. The calcified nodules were stained by Alizarin Bordeaux after 10d. The cells exposed in the SEMFs were arranged in Spiral appearance after 8d. The SEMFs exposure time at 2. Oh, 2.5h and 3. Oh significantly inhibited cell proliferation （P〈0. 01） and 0. 5h, 1. Oh, 1.5h groups more significantly than control groups （P〈0. 05）. When the 3d, 6dand 12 d the ALP activities of the 0. 5h, 1. Oh, 1.5h and 2. Oh, times group were significantly higher than those in the control group （P〈0. 05）, and after 9d the 1.0h,1.5h and 2. Oh activity of ALP higher significantly than control and other groups（P〈0. 01）. Other groups had no effect on the ALP activity. Alizarin Bordeaux staining result showed the amounts of calcified nodules 1. Oh, 1.5h and 2. Oh higher than control groups. The SEMFs at 50Hz, 1.8mTdifferent time exposure groups inhibits the proliferation of OB, but they enhances the maturation and mineralization of the OB and SEMFs at 1.8rot of the 1.5h has the strongest activity.