Doane M G
J Gen Physiol. 1967 Dec;50(11):2603-32. doi: 10.1085/jgp.50.11.2603.
By monitoring the fluorescence of the isolated giant axon of the squid Loligo pealei, it was possible to follow changes in its oxidation-reduction state as caused by the action of anoxia, cyanide, Amytal, and azide. The response to oxygen depletion was very rapid, the NAD within the axon being 90% reduced within 1-2 min. Cyanide and Amytal gave essentially similar results, although somewhat longer periods of time elapsed during their onset and washout periods. The extent of NAD reduction was essentially the same under conditions of anoxia and treatment with cyanide and Amytal. Azide was less effective in this respect, and at comparatively high levels of concentration (25-50 mM) gave values of 40% or less of the reduction observed with the other inhibitors. The application of ouabain and strophanthidin gave no observable NAD reduction. Variations in the time required to consume given quantities of dissolved oxygen before and after stimulation indicated an increase of 10-20% in oxygen uptake rate associated with activity, although this figure appeared to be a function of the surface-to-volume ratio of the axon. A biochemical analysis of axoplasm for oxidized and reduced pyridine nucleotide was made. Fluorometric examination of centrifuged axoplasm indicated that the NAD-NADH was largely confined to the mitochondria of the axon.
通过监测分离出的枪乌贼（Loligo pealei）巨大轴突的荧光，能够追踪其氧化还原状态因缺氧、氰化物、阿米妥和叠氮化物作用而发生的变化。对氧耗竭的反应非常迅速，轴突内的NAD在1 - 2分钟内90%被还原。氰化物和阿米妥给出了基本相似的结果，尽管在其起效和洗脱期经过的时间稍长。在缺氧以及用氰化物和阿米妥处理的条件下，NAD还原的程度基本相同。叠氮化物在这方面效果较差，在相对较高浓度（25 - 50 mM）时，其还原值仅为其他抑制剂所观察到的40%或更低。应用哇巴因和毒毛旋花子苷未观察到NAD还原。刺激前后消耗给定数量溶解氧所需时间的变化表明，与活动相关的氧摄取率增加了10 - 20%，尽管这个数字似乎是轴突表面积与体积比的函数。对轴浆进行了氧化型和还原型吡啶核苷酸的生化分析。对离心后的轴浆进行荧光检测表明，NAD - NADH主要局限于轴突的线粒体中。
