Voltage-sensitive dyes (VSDs) are used to record transient potential changes in various cardiac preparations. In our laboratory, action potentials have been recorded by optical probe using di-4-ANEPPS. In this study, the effects of two different ways of staining were compared in guinea pig and rabbit isolated hearts perfused according to Langendorff: staining either by coronary perfusion with low dye concentration or with concentrated dye as a bolus into the aorta. Staining with low dye concentration lead to its better persistence in the tissue. Electrogram and coronary flow were monitored continuously. During the staining and washout of the dye, prominent electrophysiological changes occurred such as a decrease in spontaneous heart rate, partial atrioventricular block and changes of ST-T segment, accompanied by a decrease in mean coronary flow. No production of hydroxyl radicals was found by HPLC which excluded significant ischemic damage of the myocardium. Good viability of the stained preparation was supported by unchanged electron microscopy. Since in rabbit hearts the VSD-induced arrhythmogenesis was less pronounced, we conclude that the rabbit myocardium is more resistant to the changes triggered by VSD application. It may be due to different properties of the membrane potassium channels in the cardiomyocytes of these two species.
- MeSH
- akční potenciály MeSH
- barvení a značení MeSH
- draslíkové kanály metabolismus MeSH
- elektrofyziologie MeSH
- financování organizované MeSH
- fluorescenční barviva toxicita MeSH
- kardiomyocyty metabolismus účinky léků MeSH
- králíci MeSH
- morčata MeSH
- myokard metabolismus ultrastruktura MeSH
- perfuze MeSH
- pyridinové sloučeniny toxicita MeSH
- srdce patofyziologie účinky léků MeSH
- srdeční arytmie chemicky indukované patofyziologie MeSH
- transmisní elektronová mikroskopie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- morčata MeSH
- zvířata MeSH
- Publikační typ
- techniky in vitro MeSH
The present paper deals with new possibility how to study ischemia and reperfusion in rabbit isolated heart perfused according to Langendorff. Electrogram was recorded by touch-less method and coronary flow measured throughout the experiment. Moreover, monophasic action potentials (MAPs) were obtained by optical probe using voltage-sensitive dye di-4-ANEPPS. Each experiment consisted from four successive periods: stabilization (control), staining with the dye, washout of the dye, flow ischemia, reperfusion. During ischemic period, typical changes of electrogram were observed and they were accompanied by corresponding changes of MAPs. In conclusion, MAPs recorded by optical method can be used as a tool for studying ischemia – reperfusion changes in isolated rabbit hearts. However, since the effects of the dye to tissue itself are under intensive investigation and not fully elucidated yet, it is necessary to be somewhat cautious about the results obtained in this way.
- MeSH
- akční potenciály MeSH
- barvicí látky diagnostické užití MeSH
- experimenty na zvířatech MeSH
- financování organizované MeSH
- ischemická choroba srdeční diagnóza patofyziologie MeSH
- králíci MeSH
- počítačové zpracování signálu MeSH
- reperfuze myokardu MeSH
- srdce fyziologie patofyziologie účinky léků MeSH
- srdeční elektrofyziologie metody MeSH
- uchovávání orgánů metody využití MeSH
- Check Tag
- králíci MeSH
