+Gz重复作用对大鼠前脑神经元的影响

目的 探讨不同G值重复暴露后大鼠脑神经元损伤及其区域分布特点。方法 将53只雄性SD大鼠随机分为对照组、＋2G，＋6Gz，＋10Gz和＋10Gy暴露组。分别在暴露后6h，1d，3d处死取脑，做石蜡或电镜超薄切片，利用光镜和电镜，观察不同G值重复暴露后，脑神经元形态学和超微结构的变化。结果 ＋2Gz重复暴露组无明显的脑神经元形态学变化。＋6Gz重复暴露后6h可见脑神经元超微结构的轻度变化，24h恢复正常。＋10Gz和＋10Gy重复暴露后，分别在海马CA1区、下丘脑、梨状皮层和左颞叶皮层、左梨状皮层，可见一定数量的变性神经元及重度的超微结构损伤。结论 高G值重复暴露可引起大鼠特定脑区的神经元损伤，可能系机械力所致。

Effect of repeated +Gz exposures on rats forebrain

AIM To investigate the area distribution peculiarity of rats brain injury after repeated +Gz exposures. METHODS 53 SD male rats were divided into control group, +2 Gz, +6 Gz, +10 Gz and +10 Gy exposure group. Rats brains were taken 6 h, 1 d or 3 d after +Gz exposure run for histopathologic and ultrastructure studies by light microscope and electron microscope. RESULTS There were not obvious changes of neuron morphology after repeated +2 Gz exposures. At 6 h after repeated +6 Gz exposures, there were gently ultrastructure changes in rats brain, and resumed at 24 h. We could find a lots of degeneration neurons with weightily ultrastructure injury at hippocampus CA1, hypothalamus, piriform cortex, and left temporal cortex and left piriform cortex after repeated +10 Gz or +10 Gy exposures. CONCLUSION There was neuron injury in special brain area after repeated high G exposure. It could be caused by mechanal force effect.