Dodd D E, Faiman M D
Biochem J. 1978 Sep 15;174(3):769-75. doi: 10.1042/bj1740769.
NADP+, NADPH and glucose 6-phosphate dehydrogenase were determined in the cerebral cortex of mice exposed to high O2 pressure for 0, 8 and 16 min. These time intervals corresponded to 0, 50 and 100% of the CT50 (the time taken for 50% of the mice to convulse). Cerebral NADP+, NADPH and glucose 6-phosphate dehydrogenase also were determined in O2-exposed mice exhibiting hyperactivity, convulsions, and in mice killed 10s after convulsions. Similar increases in cortical NADP+ and decreases in NADPH were found in mice exposed to 610kPa (6 atm.) of 100% O2 for 0, 50 and 100% of the CT50, during hyperactivity, onset of seizure and 10s after convulsions. The NADP+/NADPH ratio increased approx. 25% at 0% of the CT50, and remained at this increased value at all O2-exposure periods including the hyperactive state, onset of seizure and 10s after convulsions. Identical changes in cerebral NADP+ , NADPH and the NADP+/NADPH ratio were found in mice exposed for 16min to 100% O2 at 100, 350 or 610kPa. No change in cerebral glucose 6-phosphate dehydrogenase was found in mice exposed to 610kPa of 100% O2 during the various stages of O2 toxicity. Only in the 10s post-convulsive group was a statistically significant decrease in glucose 6-phosphate dehydrogenase observed. Disulfiram [bis(diethylthiocarbamoyl) disulphide], an effective O2-protective agent, did not prevent the O2-induced increase in cerebral NADP+ and the NADP+/NADPH ratio, or decrease in NADPH.
在暴露于高氧压力0、8和16分钟的小鼠大脑皮层中测定了NADP⁺、NADPH和葡萄糖6-磷酸脱氢酶。这些时间间隔分别对应于CT50（50%的小鼠发生惊厥所需的时间）的0、50和100%。还在表现出多动、惊厥的氧气暴露小鼠以及惊厥后10秒处死的小鼠中测定了大脑NADP⁺、NADPH和葡萄糖6-磷酸脱氢酶。在暴露于610kPa（6个大气压）的100%氧气中达到CT50的0、50和100%的小鼠中，在多动、癫痫发作开始时以及惊厥后10秒，发现皮层NADP⁺有类似增加，NADPH减少。在CT50的0%时，NADP⁺/NADPH比值增加约25%，并且在包括多动状态、癫痫发作开始和惊厥后10秒在内的所有氧气暴露时间段内都保持在这个升高的值。在暴露于100、350或610kPa的100%氧气中16分钟的小鼠中，发现大脑NADP⁺、NADPH和NADP⁺/NADPH比值有相同变化。在氧气毒性的各个阶段暴露于610kPa的100%氧气的小鼠中，未发现大脑葡萄糖6-磷酸脱氢酶有变化。仅在惊厥后10秒组中观察到葡萄糖6-磷酸脱氢酶有统计学显著下降。双硫仑[双（二乙硫代氨基甲酰）二硫化物]，一种有效的氧气保护剂，不能防止氧气诱导的大脑NADP⁺增加和NADP⁺/NADPH比值升高，以及NADPH减少。
