Stimulation of DNA synthesis in kidney epithelial cells in culture by potassium.
The hypothesis that the K+ concentration of extracellular fluid is a determinant of renal DNA synthesis was examined in quiescent, high-density cultures of monkey kidney epithelial cells of the BSC-1 line. The addition of KCl to the medium increased the number of cells engaged in DNA synthesis in a concentration-dependent manner. The capacity of K+ to stimulate DNA synthesis in a greater number of cells was additive with exogenous NaCl and calf serum and was associated with an increment in the steady-state cell K+ content. Studies with other monovalent cations indicated that the stimulatory effect of K+ on DNA synthesis was not mediated by increments in the chloride concentration or osmotic pressure of the medium. The addition of K+ to confluent cultures was associated with a concentration-dependent increase in cell multiplication. The commitment of cells to increased multiplication required exposure of the culture to added KCl for longer than 3 but not more than 6 h. Addition of KCl to cultures of mouse fibroblasts did not alter DNA synthesis, multiplication, or cell K+ content. These observations indicate that increased availability of K+ in the extracellular fluid can stimulate DNA synthesis in kidney epithelial cells in culture.
D000818:Animals; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D003470:Culture Media; D004247:DNA / Q000096:biosynthesis*; D004847:Epithelial Cells; D005110:Extracellular Space / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology; D066298:In Vitro Techniques; D007668:Kidney / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D011188:Potassium / Q000494:pharmacology*; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012965:Sodium Chloride / Q000494:pharmacology; D013268:Stimulation, Chemical; D013997:Time Factors
D003470:Culture Media; D012965:Sodium Chloride; D011189:Potassium Chloride; D004247:DNA; D011188:Potassium