中文摘要：

背景：适当强度的恒磁场可抑制血管平滑肌细胞增殖，可能用于抑制经皮冠状动脉介入治疗术后再狭窄。目的：观察不同磁感应强度恒磁场对培养的大鼠主动脉血管平滑肌细胞骨桥蛋白基因表达的影响，以探讨磁场是否能用于经皮冠状动脉介入治疗术后再狭窄的防治。设计：随机分组，对照观察。单位：解放军第四军医大学西京医院心内科。材料：实验于2006—02／12在解放军第四军医大学西京医院心内科实验室（全军心血管病研究所）完成。纯种雄性SD大鼠，体质量200-250g。方法：用含体积分数为0．1小牛血清的DMEM培养液体外培养大鼠主动脉血管平滑肌细胞，实验随机分为对照组，1Gs恒磁场组、5Gs恒磁场组、10Gs恒磁场组、50Gs恒磁场组，其中对照组不予磁场干预，其他各组分别给予磁场干预继续培养48h。应用反转录-聚合酶链反应及蛋白免疫印迹技术结合吸光度扫描分析，观察恒磁场对血管平滑肌细胞骨桥蛋白及骨桥蛋白mRNA表达的影响。主要观察指标：各组血管平滑肌细胞骨桥蛋白及骨桥蛋白mRNA的表达。结果：对照组细胞表达一定量的骨桥蛋白及骨桥蛋白基因，各恒磁场组均较对照组降低，差异显著（P〈0．05）。不同磁场强度组间分析显示，恒磁场的刺激作用具有磁场强度依赖性，随磁场强度加大，抑制骨桥蛋白及骨桥蛋白mRNA表达作用增强。结论：适当强度的恒磁场能在基因水平上抑制血管平滑肌细胞骨桥蛋白的表达，磁场对经皮冠状动脉介入治疗术后的再狭窄可能具有防治作用。

英文摘要：

BACKGROUND：Constant magnetic field of proper intensity can inhibit the proliferation of vascular smooth muscle cells and it can be used to inhibit the restenosis following peroutaneous coronary intervention. OBJECTIVE： To observe the effect of constant magnetic field of different intensities on the expression of osteopontin gene in rat aorta smooth muscle cells, so as to investigate whether magnetic field can be used to prevent and treat restenosis following percutaneous coronary intervention. DESIGN： A randomly grouping and controlled observation SETTING ： Department of Cardiology, Xijing Hospital of the Fourth Military Medical University of Chinese PLA. MATERIALS： The experiments were carried out in the laboratory of Department of Cardiology （Military Institute of Cardiovascular Disease）, Xijing Hospital of the Fourth Military Medical University of Chinese PLA from February to December in 2006. Male pure SD rats of 200-250 g were used. METHODS： Rat aorta smooth muscle cells were cultured in vitro in DMEM medium containing fetal bovine serum （0.1 in volume serum）, and then the cells were randomly divided into control group, constant magnetic field of 1, 5, 10 and 50 Gs groups, those in the control group were not treated with magnetic field, and those in the other groups were treated with magnetic field and cultured for another 48 hours. Reverse transcription-polymerase chain reaction and Western blotting were combined with absorbance （A） scanning analysis to observe the effect of constant magnetic field on the expressions of osteopontin and its mRNA in smooth muscle cells. MAIN OUTCOME MEASURES ： Expressions of osteopontin and its mRNA in smooth muscle cells RESULTS： The expressions of osteopontin and osteopontin genes in the constant magnetic field groups were significantly decreased as compared with that in the control group （P 〈 0.05）, there were also significant differences among the constant magnetic field groups of different intensities （P 〈 0.05）. It was indicated t