Mayevsky A, Shaya B
J Appl Physiol Respir Environ Exerc Physiol. 1980 Oct;49(4):700-7. doi: 10.1152/jappl.1980.49.4.700.
Hyperbaric oxygen toxicity (HPO), under various environmental and physiological conditions, was identified by measuring the electrical, hemodynamic, and metabolic activity of the awake brain in rats. The electrical activity was evaluated by the electrocorticogram; the hemodynamic and metabolic activity were measured by use of the surface fluorometry/reflectometry technique. The oxidation-reduction state of NADH (metabolic activity) was measured by using the quartz fiber-optic system to excite the tissue and transmit the fluorescence-emitted light from the brain. The hemodynamic responses were evaluated from the reflectance signal. In three sets of experiments we tested the effects of pressure level, age, and protection agents (pentobarbital and diazepam) on the various parameters measured from the brain. The results can be summarized as follows. 1) The effect of the pressure level of the toxicity process is significant; the higher the pressure, the greater the toxicity. 2) The 60-psi level of pressure is a turning point in the toxicity process, and the kinetic of the process is different below and above this point. 3) The 14-day-old rats showed resistance to the HPO exposure as compared to the older aged rats. 4) The pentobarbital and diazepam protect against the toxicity at 60 and 90 psi, as evaluated by various parameters measured.
通过测量清醒大鼠大脑的电活动、血流动力学和代谢活动，在各种环境和生理条件下确定了高压氧毒性（HPO）。电活动通过脑电图进行评估；血流动力学和代谢活动通过表面荧光测定法/反射测定法技术进行测量。使用石英光纤系统激发组织并传输大脑发出的荧光，测量NADH的氧化还原状态（代谢活动）。从反射信号评估血流动力学反应。在三组实验中，我们测试了压力水平、年龄和保护剂（戊巴比妥和地西泮）对从大脑测量的各种参数的影响。结果总结如下：1）毒性过程的压力水平影响显著；压力越高，毒性越大。2）60磅力/平方英寸的压力水平是毒性过程中的一个转折点，该点以下和以上过程的动力学不同。3）与老年大鼠相比，14日龄大鼠对HPO暴露具有抗性。4）根据测量的各种参数评估，戊巴比妥和地西泮在60和90磅力/平方英寸时可预防毒性。
