Background: Ischemia-reperfusion injury is the leading cause of early dysfunction following transplantation. Currently, there are no techniques available to accurately measure ischemic changes during organ storage. Therefore, the interest exists in developing non-invasive monitoring techniques. We used NADH and tryptophan as fluorescent markers, since both are intrinsic fluorophores and excellent indicators for levels of hypoxia and protein denaturation, respectively. Experimental Design: We used cavity-dumped dye lasers to perform time-resolved fluorescence measurements of ischemic, intact rabbit myocardium, in order to examine whether this method would provide sufficient signal in a pilot study. Results: Multi-component decays were measured for time-resolved fluorescence changes in both NADH and tryptophan over the course of 3 hours. NADH showed a general increase in mean-lifetime, while the majority of the unbound form decreased from 0.4 to 0.28 ns. Tryptophan had a slight mean-lifetime decrease from 4 to 3.8 ns. Conclusions: Strong signals were obtained with easily resolved component lifetimes. Future studies will attempt to elaborate the correlation between organ viability and fluorescence-based signals using lifetime analyses, anisotropy studies and the application of two-photon excitation measurements.
|Number of pages||6|
|Journal||Proceedings of SPIE - The International Society for Optical Engineering|
|State||Published - 1 Jan 1999|
|Event||Proceedings of the 1999 Biomedical Imaging: Reporters, Dyes, and Instrumentation - San Jose, CA, USA|
Duration: 26 Jan 1999 → 28 Jan 1999