在高压氧下豚鼠听觉诱发电位的变化

豚鼠暴露在两个绝对压下呼吸高压氧,比较了暴露前后短声诱发的听神经动作电位(AP)、脑干电位(BSEP)及听皮层电位(ACEP)的潜伏期和振幅。主要结果是:在呼吸高压氧期间AP和BSEP的振幅明显增高,但ACEP的振幅并不完全与AP和BSEP呈同步性改变;在高压氧下约半数动物的ACEP振幅增高,但其余动物的却呈现减低或无明显改变。这可能反映皮层对高压氧较为敏感,而且个体间敏感程度又不相同。实验结果提示,在两个绝对压下呼吸高压氧1小时对改善听觉系统的功能是有益的。

CHANGES OF AUDITORY EVOKED POTENTIALS IN GUINEA PIGS UNDER HYPERBARIC OXYGEN CONDITIONS

Changes of auditory nerve action potential (AP), brainstem evoked potential (BSEP) and auditory cortical evoked potential (ACEP) in guinea pigs were studied before, during and after hyperbaric oxygen(HBO) exposure at 2 atm (absolute). In comparison with the pre-exposure levels, the amplitudes of AP and BSEP during the stay of HBO were significantly increased. The amplitude of ACEP under HBO conditions, however, did not show synchronous change-completely with the amplitudes of AP and BSEP. In about half of the animals, the ACEPs showed increase in amplitude, but in others the ACEPs showed decrease or on changes in amplitude, even though the AP ans BSEP manifested synchronous increase in amplitudes. This seems to indicate that the cortex is more sensitive to HBO and the sensitivity varied with the individual. animals. The experiments suggest that breathing HBO at 2 atm (absolute) for 1 hour is beificial to the improvement of the auditory functions.