Coremans J M, Ince C, Bruining H A, Puppels G J
Department of General Surgery, Erasmus University Rotterdam, The Netherlands.
Biophys J. 1997 Apr;72(4):1849-60. doi: 10.1016/S0006-3495(97)78831-3.
In vivo analysis of the metabolic state of tissue by means of reduced nicotinamide adenine dinucleotide (NADH) fluorimetry is disturbed by tissue movements and by hemodynamic and oximetric effects. These factors cause changes in the absorption of ultraviolet (UV) excitation light by the tissue. Many different methods have been used in the literature to compensate measured NADH fluorescence intensities for these effects. In this paper we show on theoretical grounds that the ratio of NADH fluorescence intensity and UV diffuse reflectance intensity provides a (semi-)quantitative measure of tissue NADH concentrations. This result is corroborated by experiments with tissue phantoms in which absorption and back-scattering properties were varied. Furthermore, we have verified the validity of this compensation method in isolated Langendorff-perfused rat heart preparations. In this preparation oximetric effects (of blood and tissue) are the major determinants of the metabolism-dependent UV diffuse reflectance change. Hemodynamic effects accompanying compensatory vasodilation are negligible. Movement artifacts were eliminated by simultaneously recording fluorescence and reflectance images, using a CCD camera with a biprism configuration. The results show that the NADH fluorescence/UV reflectance ratio can be used to monitor the mitochondrial redox state of the surface of intact blood-perfused myocardium.
通过还原型烟酰胺腺嘌呤二核苷酸（NADH）荧光法对组织代谢状态进行的体内分析会受到组织运动以及血液动力学和血氧测定效应的干扰。这些因素会导致组织对紫外（UV）激发光的吸收发生变化。文献中已使用许多不同方法来补偿这些效应所导致的测得的NADH荧光强度。在本文中，我们从理论依据表明，NADH荧光强度与UV漫反射强度之比提供了一种（半）定量测量组织NADH浓度的方法。这一结果在吸收和后向散射特性不同的组织模型实验中得到了证实。此外,我们已经在离体Langendorff灌注大鼠心脏标本中验证了这种补偿方法的有效性。在此标本中，（血液和组织的）血氧测定效应是代谢依赖性UV漫反射变化的主要决定因素。伴随代偿性血管舒张的血液动力学效应可忽略不计。通过使用具有双棱镜配置的CCD相机同时记录荧光和反射图像，消除了运动伪影,结果表明，NADH荧光/UV反射率比值可用于监测完整血液灌注心肌表面的线粒体氧化还原状态。
