正弦波电磁场对大鼠椎间盘纤维环细胞的生物学影响

Electromagnetic fields and the proliferation and matrix synthesis of annulus fibrosus cells

目的研究低频正弦波电磁场对大鼠椎间盘纤维环细胞增殖和细胞外基质的生物学影响。方法体外培养大鼠生长良好的椎间盘纤维环细胞，取生长良好的第3代细胞，随机分为实验组和对照组，实验组采用75Hz正弦波电磁场的间断刺激，对照组置于同样培养条件下但不暴磁。通过流式细胞术和四甲基偶氮唑蓝（MTT）法检测细胞周期和增殖活性，逆转录聚合酶链反应（RT—PCR）检测椎间盘细胞胶原和蛋白聚糖（aggre-can）的表达情况，AlcianBlue法检测糖胺多糖（sGAG）含量。结果暴磁刺激初期细胞增殖效果不明显，刺激天数〉4d时能显著促进细胞增殖（P〈0．05），与对照组相比，实验组细胞Ⅰ、Ⅱ型胶原、蛋白聚糖的表达水平均显著上调（P〈0．05），GAG含量也增加。结论正弦波电磁场可以促进纤维环细胞的增殖，上调正常椎间盘细胞外基质Ⅰ、Ⅱ型胶原、蛋白聚糖的表达水平和GAG含量，可望为治疗椎间盘退变提供一种新的思路。

Objective To study the biological effects of sinusoidal electromagnetic fields （EMFs） on prolifer- ation and extracellular matrix （ECM） formation by annulus fibrosus （AF） cells in rats. Methods AF cells isolated from rats were randomly divided into a control group and an experimental group. The cells in the experimental group were stimulated with an EMF, while those in the control group were held under the same culture conditions but with no EMF. Flow cytometry and MTT were performed to observe the effects on the cell cycle and proliferation. Collagen and aggrecan expression were examined after amplification with a reverse transcriptase polymerase chain reaction （ RT- PCR）. Sulfated glycosaminoglycan （sGAG） content was detected by applying the Alcian blue method. Results AF cell proliferation was not significant until after 4 days of stimulation. Compared with the control group, the expression of type Ⅰ and Ⅱ collagen and Aggrecan were up-regulated, and sGAG content was increased in the experimental group. Conclusion AF cell proliferation was enhanced by EMF. Gene expression of collagen type I and Ⅱ and Aggrecan in- creased, as well as sGAG levels. The results suggest an approach for treating of intervertebral disc degeneration.