目的:观察头低位模拟失重状态下正常人视觉电生理的变化。方法:男性健康志愿者6例,-6°头低位卧床模拟失重状态,在受试前、受试第2,5d测量双眼的视觉诱发电位和视网膜电图。按照国际视觉电生理协会的临床电生理标准(2008年修订),记录高、中、低3种空间频率下的图形视觉诱发电位(P-VEP),以及国际标准下的视杆细胞反应、最大混合反应、振荡电位、视锥细胞反应和30Hz闪烁光反应。结果:P-VEP中P100波潜伏期在各种空间频率下均无显著改变,波幅在高空间频率下在受试前及受试第2,5d之间有显著改变,差异具有统计学意义(P<0.05),在中、低空间频率下无显著差异。在视网膜电图中,视锥细胞反应及闪烁光反应在受试前后无显著变化(P>0.05);视杆细胞反应及最大混合反应波的潜伏期在受试前及受试第2d之间有显著改变(P<0.05),而波幅无明显改变(P>0.05);振荡电位总和波波幅在受试前后无显著改变(P>0.05)。结论:头低位卧床模拟失重状态下可导致人视觉诱发电位及视网膜电图的改变,从而影响正常人视觉功能。

AIM:To observe the influence of head down tilt simulated weightlessness on electrophysiology of vision. ·METHODS:Head-down tilt for -6° was adopted in 6 healthy volunteers. Pattern visual evoked potential (P-VEP) under different space frequency,flash electroretino-graphy (ERG),including rod response,maximal res-ponse,cone response,oscillatory potentials (OPs) and 30Hz flicker were recorded,and the latency and amplitude from each wave were analyzed before,two days and five days after trial. The record procedure followed the ISCEV standard for full-field clinical ERG (2008 update). ·RESULTS:No significant difference was detected in the latencies of P100 under different space frequency. The amplitude of P100 had significant change under high space frequency between pre-test and 2,5 days after test (P<0.05). But not the same happened in middle and low space frequency. No significant differences were detected in the latencies and amplitudes of cone response and 30 Hz flicker among various time points(P>0.05). The latencies were significantly prolonged in rod and maximal responses between pre-test and 2 days after test (P<0.05),but no obvious change was found in amplitudes(P>0.05). There were no significant differences detected in the ∑OPs (P>0.05). ·CONCLUSION:Head-down tilt simulated weightlessness induce the abnormality of VEP and ERG which influence the visual function of healthy people.

R85

中国全军“十一五”科技攻关资助项目(No.06G003)~~