[A comparative analysis of the intracellular potassium content for the cardiomyocyte in papillary muscle tissue and in a primary heart culture].
This work was aimed to examine potassium contents in heart myocytes. The intracellular concentration of this element was measured with electron probe microanalysis (EPMA). The cardiomyocyte was studied in samples of the papillary muscle tissue and in heart primary culture. The low temperature fixation was applied to the sample preparation. As a result, cells of the primary heart culture were shown to be separated into three kinds of myocytes, defined by their different shape, size and cellular potassium content. The rod cardial cell, to be used for electrophysiological assays, has potassium and sodium concentrations close to those of the papillary muscle. The difference in potassium concentrations is to be explained presumably by the injury of cell membrane during the primary culture preparation. Healing over the membrane is likely to parallel with the membrane damage resulting from a continuous destruction of the cellular assembly in primary culture.