Effects of voltage sensitive dye di-4-ANEPPS on guinea pig and rabbit myocardium

Effects of voltage sensitive dye di-4-ANEPPS on guinea pig and rabbit myocardium

článek v časopise - ostatní, Jost

čeština

Voltage-sensitive dyes (VSD's) are used in basic cardiology research to record transient potential changes in various cardiac preparations. In our laboratory, action potentials (APs) are recorded by optical probe using di-4-ANEPPS. In this study, the effects of two different ways of staining with this VSD were compared in guinea pig and rabbit isolated hearts perfused according to Langendorff. Staining was done either by coronary perfusion with low dye concentration or with bolus injection of highly concentrated dye into the aorta. Electrogram and coronary flow were followed continuously. During the staining and washout from dye, prominent electrophysiological changes occurred such as decrease of spontaneous heart rate, partial AV block and changes of ST-T segment, accompanied with decrease in mean coronary flow. No production of hydroxyl radicals was found by HPLC which excluded putative ischemic damage of myocardium. Good viability of stained preparation was proved by electron microscopy. Since in rabbit hearts the impact of VSD was less pronounced, we conclude that rabbit myocardium is more resistant to the changes triggered by VSD application. It may be caused by different potassium channels in the membrane of cardiomyocytes in these two species. Staining with low dye concentration leads to its better persistence in the tissue.

Voltage-sensitive dyes (VSD's) are used in basic cardiology research to record transient potential changes in various cardiac preparations. In our laboratory, action potentials (APs) are recorded by optical probe using di-4-ANEPPS. In this study, the effects of two different ways of staining with this VSD were compared in guinea pig and rabbit isolated hearts perfused according to Langendorff. Staining was done either by coronary perfusion with low dye concentration or with bolus injection of highly concentrated dye into the aorta. Electrogram and coronary flow were followed continuously. During the staining and washout from dye, prominent electrophysiological changes occurred such as decrease of spontaneous heart rate, partial AV block and changes of ST-T segment, accompanied with decrease in mean coronary flow. No production of hydroxyl radicals was found by HPLC which excluded putative ischemic damage of myocardium. Good viability of stained preparation was proved by electron microscopy. Since in rabbit hearts the impact of VSD was less pronounced, we conclude that rabbit myocardium is more resistant to the changes triggered by VSD application. It may be caused by different potassium channels in the membrane of cardiomyocytes in these two species. Staining with low dye concentration leads to its better persistence in the tissue.

di-4-ANEPPS, myocardium, rabbit, guinea pig

di-4-ANEPPS, myocardium, rabbit, guinea pig

NOVÁKOVÁ, M.; KOLÁŘOVÁ, J.; PROVAZNÍK, I.; TÁBORSKÁ, E.

2008

24. 1. 2008

0231-5882

General Physiology and Biophysics

26

1

Slovenská republika

45

54

10