caa a22 4500 475790952 CHVBK 20180406123710.0 cr unu---uuuuu 170329e20000701xx s 000 0 eng 10.1007/s004239900100 doi (NATIONALLICENCE)springer-10.1007/s004239900100 Attitude of patients toward transplantation of xenogeneic organs [Elektronische Daten] [M. Steinbauer, Anthony Gustav Harris, Christoph Abels, Konrad Messmer] Intravital microscopy is widely used to study the microcirculation. However, the use of fluorescent dyes can induce phototoxic effects which may affect the measurements, particularly in tissue exposed to oxidative stress. The aim of the study was to determine the threshold light dose at which fluorescent microscopy is associated with phototoxic effects in the hamster dorsal skinfold chamber under normal and pathological conditions. The extent of phototoxicity in the microcirculation in the hamster skinfold chamber was investigated using intravital fluorescent microscopy during 60 min of illumination (1048 mW/cm2) applying two different concentrations of fluorescein isothiocyanate dextran under baseline conditions (groups A and B) and following 4 h of ischemia (groups C and D). In the second part of the study the microvasculature was analyzed regarding phototoxic effects during a standardized intravital microscopic examination after 4 h of pressure induced ischemia. Groups I and II (n=7) were studied using epiillumination after injection of fluorescein isothiocyanate dextran plus rhodamine 6G or rhodamine 6G only. In group III (n=7) only transillumination was used. Arteriolar vasospasm, microvascular perfusion failure, thrombus formation, and enhanced leukocyte endothelium interaction were observed as signs of a phototoxic effect in normal tissue. However, the light doses needed to induce these effects clearly exceeded those during standard examinations. The induction of a 4-h ischemia and reperfusion further enhanced these effects. Despite the predamage by ischemia/reperfusion the comparison of epiillumination and transillumination microscopy using a standard protocol showed no differences regarding the parameters analyzed at any time. This indicates that epiillumination and the fluorescent dyes per se did not affect the experimental results. These results show that ischemia/reperfusion studies in the dorsal skinfold chamber of the Syrian golden hamster can be carried out safely without the risk of inducing phototoxic effects by fluorescent microscopy. Nevertheless every laboratory using epiillumination and fluorescent dyes should take precautions to avoid these effects by the use of sensitive cameras to lower the light dose Springer-Verlag, 2000 Key words Ischemia/reperfusion nationallicence Phototoxicity nationallicence Rhodamine 6G nationallicence Fluorescein isothiocyanate dextran nationallicence Intravital microscopy nationallicence Steinbauer M. Institute for Surgical Research, University of Munich, Germany, Germany aut Harris Anthony Gustav Institute for Surgical Research, University of Munich, Germany, Germany aut Abels Christoph Institute for Surgical Research, University of Munich, Germany, Germany aut Messmer Konrad Institute for Surgical Research, University of Munich, Germany, Germany aut Langenbeck's Archives of Surgery Springer-Verlag 385/4(2000-07-01), 306-306 1435-2443 385:4<306 2000 385 423 https://doi.org/10.1007/s004239900100 text/html Onlinezugriff via DOI 1 review-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s004239900100 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Steinbauer M. Institute for Surgical Research, University of Munich, Germany, Germany aut NATIONALLICENCE 700 1- Harris Anthony Gustav Institute for Surgical Research, University of Munich, Germany, Germany aut NATIONALLICENCE 700 1- Abels Christoph Institute for Surgical Research, University of Munich, Germany, Germany aut NATIONALLICENCE 700 1- Messmer Konrad Institute for Surgical Research, University of Munich, Germany, Germany aut NATIONALLICENCE 773 0- Langenbeck's Archives of Surgery Springer-Verlag 385/4(2000-07-01), 306-306 1435-2443 385:4<306 2000 385 423 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer