利用微孔板荧光分析仪结合线粒体膜电位特异性荧光探针罗丹明123测量了内外源性一氧化氮对癌细胞线粒体膜电位的影响。实验结果显示添加一氧化氮供体后，荧光强度快速增大，且在较长的一段时间内保持不变，而对照组的荧光强度没有明显变化；此外，加载荧光探针前用一氧化氮合酶抑制剂和一氧化氮供体孵育24 h分别能降低和提高线粒体膜电位。研究结果表明增加内外源性一氧化氮均能提高线粒体膜电位，这对于在细胞器水平认识一氧化氮参与促进癌细胞增殖与转移的过程具有一定的意义。

The effects of endogenous and exogenous nitric oxide on cancer cell mitochondrial membrane potential are studied by combining microplate fluorescence analyzer and special fluorescence probe rhodamine 123. Results show that the fluorescence intensity increases rapidly and keeps at a high level for a quite long period after nitric oxide donor is injected into the cells, while the fluorescence intensity of control group do not change significantly. Moreover, incubation with nitric oxide synthase inhibitor or nitric oxide donor for 24 hours prior rhodamine 123 loading can decrease or increase mitochondrial membrane potential, respectively. These results indicate that the increase of endogenous or exogenous nitric oxide can lift up the potential of mitochondrial membrane. It will be helpful to understand the role of nitric oxide in promoting cancer cell proliferation and metastasis at organelle level.