[Dependence of ion transport across the plasma membrane on cell culture density. II. Active and passive cation transport during the growth of L cell cultures].
Rubidium and lithium influxes as well as intracellular potassium and sodium contents were investigated in L cells during the culture growth. In sparse culture over the cell densities 0.5-3 X 10(4) cells/cm2 ouabain-sensitive rubidium influx is small and ouabain-resistant lithium influx in high. With the increase in culture density up to 4-5 X 10(4) cells/cm2 the active rubidium influx, mediated by ouabain-sensitive component, is enhanced, and ion "leakage" tested by lithium influx is diminished. Simultaneously with the exponential growth of culture the intracellular potassium content is increased and the intracellular sodium content is decreased resulting in the higher K/Na ratio in cell. During the further transition to dense culture and in stationary state (10-17 X 10(4) cells/cm2) the sodium content and lithium influx do not change significantly, but the potassium content is decreased. The decrease in intracellular potassium is correlated with that in the portion of cells in S-phase from 27-30 to 12%. Thus, in transformed cells the density-dependent alterations in membrane cation transport are observed.
I I
II
Marakhova
K V
KV
Sal'nikov
T A
TA
Vinogradova
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D001693:Biological Transport, Active / Q000187:drug effects; D002452:Cell Count / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D002712:Chlorides / Q000378:metabolism; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism*; D007739:L Cells / Q000187:drug effects / Q000378:metabolism*; D008094:Lithium / Q000378:metabolism; D018021:Lithium Chloride; D051379:Mice; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism*; D012413:Rubidium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D013997:Time Factors
D002712:Chlorides; D007473:Ion Channels; D010042:Ouabain; D008094:Lithium; D012964:Sodium; D018021:Lithium Chloride; D012413:Rubidium; C032710:rubidium chloride; D011188:Potassium
Zavisimost' transporta ionov cherez plazmaticheskuiu membranu ot plotnosti kletochnoĭ kul'tury. II. Aktivnyĭ i passivnyĭ transport kationov po khodu rosta kul'tur kletok L.