8 Hz/130 dB次声对大鼠心肌细胞的损伤作用研究

目的观察次声对大鼠心肌的影响并探讨其相关机制。方法用8Hz／130dB的次声分别作用大鼠1，7，14，21和28d，每日2h，观察大鼠心肌细胞超微结构的变化和心肌的凋亡情况以及次声引起的心肌氧化损伤。结果与对照组比较，次声暴露组大鼠心肌超微结构出现损伤；心肌细胞凋亡增加（P〈0.01）；心肌组织MDA含量增加（P〈0．01），SOD含量降低（P〈0．01），心肌出现氧化损伤。这些损伤性变化随时间的延长而逐渐加重。结论次声可引起大鼠心肌损伤，损伤程度与次声暴露时间有关。

Effects of infrasound on rat myocardial cell and its underlying mechanism

Objective To observe the effects of infrasound on rat myocardial cells and to study its underlying mechanism. Methods One hundred Sprague-Dawley rats were divided into a normal control group and a infrasound exposure group, composed of various subgroups subject to exposure to infrasound for 2 hours daily for 1 d,7 d,14 d,21 d,and 28 d, respectively. The ultra-microstructure and apoptosis of the rat myocardial cells were observed, and SOD and MDA were measured. Results After exposure to infrasound, significant ultra-microstructural impairment and increased apoptosis of the myocardial cells were observed in the infrasound exposure group as compared to those of the normal control group,(P<0.01), there also observed significant time-dependent increase of MDA and significant time-dependent decrease of SOD in the rat myocardial cells(P<0.01). Conclusion Infrasound can induce damage to the rat cardiac muscle cells dependent on the exposure time to infrasound.