电磁脉冲诱导大鼠心肌闰盘间隙开放及其机制

Effect of EMP on heart intercalated discs gap in rats and its possible mechanism

目的探讨电磁脉冲（EMP）诱导心肌闰盘（ID）的改变及其作用机制。方法用EMP模拟发生器，场强为50～400kV／m，脉冲次数200次，雌性SD大鼠30只，随机分为5组，每组6只。照后12h时采用硝酸镧示踪法和透射电子显微镜观察心肌ID结构的改变，用基因芯片检测受照心肌差异基因表达谱。结果照后12h，辐照组的ID间隙随着EMP场强的增加而逐渐增宽，ID间隙中沉积的镧颗粒随着EMP场强的增加而逐渐增多。200kV／m组与对照组相比差异表达基因有108个，其中表达上调基因有synaptorin、VGF、HSP70等51条，下调基因有NAD、FGF、Tff3等57条。结论在场强为50～400kV／mEMP范围内辐照可诱导心肌ID间隙开放，且随场强的增加而增宽，以400kV／m时最为显著，受照心肌有108个基因差异表达。

Objective To investigate the effect of electromagnetic pulse （EMP） on the the link-structure of heart intercalated discs（ID）, and to explore the mechanism involved. Methods EMP was provided by the EMP simulator of our department, the parameters was as following： 200 pulse, different field intensity（50 - 400 kV/m） . The research objects were female SD rats, they were randomly divided into five groups, each group has six rats. At 12 h after EMP exposure, the lanthanum nitrate tracer method and the transmission electron microscope （TEM） were used to observe the structural changes of left ventricular myocardium. Microarray was used to evaluate the gene differential expression of left ventricular myocardium. Results At 12 h after EMP exposure, the width of ID gap was widen gradually with field augmentation, lanthanum nitrate in ID gap was incrsased gradually with field augmentation. Compared with the control group, there were 108 genes standard altered in gcne expression profile in rat myocardium after EMP in the 200 kV/m group. 51 genes （synaptorin, VGF, HSP70, etc.） were up-regulated while 57 genes （NAD, FGF, Tff3, etc.） were down-regulated. Conclusions Space between intercalated discs was wided along with field augmentation after EMP exposureed. The changes in ID of cardiac muscle was remarkable at 400 kV/m. There were 108 genes altered in gene expression profile in rat myocardium after EMP.