Snell J C, Colton C A, Chernyshev O N, Gilbert D L
Department of Physiology and Biophysics, Georgetown University Medical School, Washington, DC, USA.
Free Radic Biol Med. 1996;20(3):361-3. doi: 10.1016/0891-5849(96)02083-7.
The Griess reaction is widely used to measure the cellular production of NO by detecting the supernatant levels of nitrite. Ordinarily, background levels of nitrite in the media are subtracted from the levels of nitrite produced by the cells by preparing a "blank" during the determination of the standard curve. Although this method is adequate for most experimental conditions, it cannot be used when cell supernatants are collected from multiwell dishes, particularly when low amounts of NO are produced and when long incubation periods are required to induce NO production. Our data show that a highly variable level of nitrite is found in the absence of cells in the media from wells at the edges of the 96-well plate while media from interior wells shows no detectable nitrite accumulation. The most likely source of this noncellular NO is from nitric oxides (NOx) found in the ambient air and reduction of air exchange or regulation of the gaseous environment eliminates this "border effect."
格里斯反应通过检测亚硝酸盐的上清液水平，被广泛用于测量细胞产生一氧化氮（NO）的量。通常，在绘制标准曲线时，通过制备“空白”对照，从细胞产生的亚硝酸盐水平中减去培养基中亚硝酸盐的背景水平。尽管这种方法适用于大多数实验条件，但当从多孔板收集细胞上清液时，特别是当产生的NO量较少且需要较长孵育时间来诱导NO产生时，该方法就不适用了。我们的数据表明，在96孔板边缘孔的培养基中，即使没有细胞，也会发现亚硝酸盐水平高度可变，而内部孔的培养基中未检测到亚硝酸盐积累。这种非细胞来源的NO最可能的来源是环境空气中的氮氧化物（NOx），减少空气交换或调节气体环境可消除这种“边缘效应”。
