静磁场辐射对大鼠心脏功能和结构的影响研究

Effects of static magnetic field radiation on the structure and function of rats′ hearts

目的研究静磁场辐射对大鼠心脏生理功能与组织结构的影响,为静磁场辐射损伤机制研究奠定基础。方法将20只Wistar雄性大鼠置于600 mT的静磁场中,每天辐射12 h,连续7 d。大鼠于辐射后7 d和14 d检测心率和心电图变化后活杀,取心肌组织入10%甲醛缓冲溶液固定、石蜡包埋、HE染色,光镜观察心脏组织结构改变。结果 600 mT静磁场辐射后7 d,大鼠心电图显示心率显著下降(P<0.01),P波时程以及T-H较对照组显著升高(P<0.05或0.01);辐射后14 d,大鼠心率以及R-H较辐射前显著下降(P<0.01),而T-H较辐射前显著升高(P<0.05)。600 mT静磁场辐射后7 d,大鼠室间隔及心内膜下心肌细胞嗜酸性变、肌纤维凝聚,核固缩;心肌纤维呈波浪状排列;血管扩张、淤血,管腔内见血浆蛋白和红细胞混杂,示血栓形成;辐射后14 d,上述病变进一步加重。结论 600 mT静磁场辐射可对大鼠心脏功能和结构造成损伤,表现为心电图异常、心脏血液循环障碍,心肌细胞变性和坏死,并在辐射后2周内呈加重趋势。

Objective To investigate the effect of static magnetic field radiation on the structure and function of rats′ hearts so as to contribute to the research on the mechanisms of static magnetic field radiation injury.Methods A total of 20 male Wistar rats were randomized into control group and static magnetic field radiation group.Rats in the radiation group were kept in the 600 mT static magnetic field for 12 hours per day and lasted for 7 days.After the heart rate and cardiogram were detected,these rats were sacrificed and specimens were harvested on the 7th and 14th day after radiation.Rats′ hearts were fixed by 10% formalin,embedded by paraffin and stained with HE before the structure of heart was observed by light microscope.Results On the 7th day after radiation,the heart rates were decreased while P phase prolonged and T-H increased significantly（P〈0.05 or 0.01）.On the 14th day after radiation,the heart rates and R-H were decreased while T-H increased（P〈0.01）.On the 7th day after radiation,the cardiac muscle cells showed eosinophilic degeneration,fiber agglomeration and pyknosis.The cardiac muscle fibers were wavy while the blood vessel was with dilation,hyperemia and thrombosis.On the 14th day after radiation,these pathological changes were intensified.Conclusion The structure and function of rats′ hearts are injured by 600 mT static magnetic field radiation.The abnormal cardiogram,blood circulation dysfunction,cardiac muscle degeneration and necrosis are detected.The injury becomes more severe within 2 weeks after radiation.