[Changes in the alkaline cation transport across the plasma membrane of CHO-K1 cell lines resistant to ethidium bromide].
Sodium and potassium intracellular concentration, rate constants of sodium and potassium and rubidium influx were determined for cultured CHO-K1 cell lines, both sensitive and resistant to ethidium bromide. The emission technique was used to measure cation fluxes into potassium and sodium-free magnesium medium. Ethidium bromide sensitive and resistant cell have similar potassium concentrations, whereas sodium concentration in the latter is by almost 2.5 times higher than that in the former. A wide range of changes both in ouabain-sensitive and ouabain-resistant fluxes was found in resistant cells: the ouabain-inhibited rubidium influx is by 3-5 times lower, the ouabain-sensitive sodium efflux is practically absent, and ouabain-inhibited potassium efflux appears. In resistant cells the ouabain-insensitive influx of rubidium is decreased by almost 2 times. It is assumed that the selection of cells for resistance to ethidium bromide is accompanied by ":pleiothypic" changes of cell membrane, involving both active and passive cation transport.
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured / Q000378:metabolism*; D006224:Cricetinae; D003412:Cricetulus; D004996:Ethidium / Q000037:antagonists & inhibitors*; D008274:Magnesium / Q000378:metabolism; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism*; D012413:Rubidium / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D013997:Time Factors
D010042:Ouabain; D012964:Sodium; D004996:Ethidium; D008274:Magnesium; D012413:Rubidium; D011188:Potassium
izmenenie transport shchelochnykh kationov cherez plazmaticheskuiu membranu kletok linii CHO-K1, ustoĭchivykh k bromistomu étidiiu.