摘要
目的探讨电磁脉冲(EMP)致体外培养的海马神经元损伤的机制及药物防护的可能性。方法EMP的照射条件为6×104V·m-1,脉冲上升时间为20ns,脉宽为30μs,频率为2.5脉冲·min-1,作用时间为2min。原代培养的海马神经元经过MK801和尼非地平预处理后进行EMP照射,采用MTT法对细胞活力进行测定;FACS法检测细胞凋亡率;Fluo-3-AM荧光探针负载、激光共聚焦显微镜扫描测定海马神经元胞内游离钙离子〔Ca2+〕i浓度。结果MK801组和MK801+尼非地平组反应细胞增殖活力的吸光度分别为0.25±0.06和0.27±0.07,明显高于单纯EMP照射组(0.17±0.08,P<0.05);MK801+尼非地平组的细胞凋亡率(53.69±13.60)%较单纯EMP组(68.63±9.04)%明显下降(P<0.05);EMP照射引起〔Ca2+〕i荧光强度显著升高(107.34±26.14,P<0.05),MK801预处理使之有所下降(81.29±19.96,P<0.05),而MK801与尼非地平联合用药可使〔Ca2+〕i荧光强度进一步下降(69.82±25.54,P<0.05)。结论MK801和尼非地平预处理可以部分地阻断EMP所致的海马神经元损伤;细胞内钙超载在EMP损伤机制中起到重要作用。
Objective To investigate the mechanism of electromagnetic pulse(EMP)-induced injury of hippocampal neurons in vitro as well as the possibility of protection by medicine. Methods Primary hippocampal neurons in vitro were exposed to EMP radiation (6×10~4V·m^(-1), rise time 20ns,pulse width 30 μs,frequency 2.5 pulses·min^(-1) for 2 min) after pretreated with MK 801(NMDAR antagonist) and nifedipine(L-calcium ion channel blocker). Then the rate of survival and apoptosis in neurons were detected with MTT and FACS respectively. Fluo-3-AM fluorescent probe and laser scanning confocal microscopy were employed to detect 〔Ca^(2+)〕i in neurons as well. Results The survival rate expressed by absorption value in KM 801 and MK 801+nifedipine group〔(0.25±0.06) and (0.27±0.07) respectively〕 were higher than that in EMP control group(0.17±0.08, P<0.05). The apoptosis rate in MK 801+nifedipine group(53.69±13.60) was lower than that in EMP control group(68.63±9.04,P<0.05).The fluorescence intensity in MK 801 and MK801+nifedipine group〔(81.29±19.96) and (69.82±25.54) respectively〕 were lower than that in EMP control group(107.34±26.14,P<0.05). Conclusion Pretreatment with MK801 and nifedipine can partly block EMP-induced injury of hippocampal neurons in vitro. Overloading of Ca^(2+) may play an important role in the injury of electromagnetic pulse on hippocampal neurons.
出处
《解放军预防医学杂志》
CAS
北大核心
2005年第3期171-174,共4页
Journal of Preventive Medicine of Chinese People's Liberation Army
关键词
电磁脉冲
海马神经元
药物防护
electromagnetic pulse
hippocampal neurons
protection
