Pflügers Archiv

, Volume 407, Issue 2, pp 153–157 | Cite as

Influence of potassium depletion on potassium conductance in proximal tubules of frog kidney

  • G. Messner
  • G. Stulnig
  • W. Rehwald
  • F. Lang
Transport Processes, Metabolism and Endocrinology; Kidney, Gastrointestinal Tract, and Exocrine Glands


In order to test for the contribution of intracellular potassium activity to the link of sodium/potassium-ATPase activity and potassium conductance, studies with conventional and potassium selective microelectrodes were performed on proximal tubules of the isolated perfused frog kidney. The peritubular transference number for potassium (tk), i.e., the contribution of peritubular slope potassium conductance to the slope conductance of the cell membranes (luminal and peritubular), was estimated from the influence of peritubular potassium concentration on the potential difference across the peritubular cell membrane (PDpt). During control conditions,PDpt is −65±1 mV, intracellular potassium activity (Ki) 57±2 mmol/l andtk 0.41±0.05. The resistance in parallel of the luminal and peritubular cell membranes (Rm) is 44±4 kΩcm, the resistance of the cellular cable (Rc) 137±13 MΩ/cm. When the cells are exposed 10 min to potassium free perfusates (series I),PDpt increases by −28±3 mV within 2 min and then decreases gradually to approach the control value within 10 min.Ki decreases by 22±3 mmol/l andRc increases by 35±10%. After a transient decrease,Rm increases by 36±9%. Readdition of peritubular potassium leads to a transient increase ofPDpt, a gradual decrease ofRm andRc as well as a gradual increase ofKitk recovers only slowly to approach 65±8% of control value within 3 and 79±10% within 6 min. When the cells are exposed 10 min to potassium free perfusates containing 1 mmol/l barium (series II),PDpt depolarizes by +28±4 mV andKi decreases by 7±1 mmol/l within 10 min. Within 2 min of reexposure to control perfusatesPDpt approaches the control recovers significantly faster than in series I and approaches 92±8% of control value within 3 min and 107±8% within 6 min reexposure to control perfusates. In conclusion, the effect of potassium free perfusates on peritubular potassium conductance depends on the degree of potassium depletion of the cell.

Key words

Potassium depletion Intracellular potassium activity Cell membrane potential Cell membrane resistance Potassium conductance Proximal tubule Amphibian kidney Barium 


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  1. 1.
    Anner BM (1981) A K-selective cation channel formed by Na−K-ATPase in liposomes. Biochem Int 2:365–371Google Scholar
  2. 2.
    Blum BM, Hoffman JF (1971) The membrane locus of Ca-stimulated K transport in energy depleted human red blood cells. J Membr Biol 6:315–328Google Scholar
  3. 3.
    Boulpaep, EL, Sackin H (1979) Equivalent electrical circuit analysis and rheogenic pumps in epithelia. Fed Proc 38:2030–2036Google Scholar
  4. 4.
    Cohen B, Giebisch G (1984) Relationship between potassium conductance and transport in renal tubular epithelium. In: Passow H, Heinz E (eds) Biological membrane — information and energy transduction. Alan R. Liss, Inc., New YorkGoogle Scholar
  5. 5.
    Froemter E (1982) Electrophysiological analysis of rat renal sugar and amino acid transport. I. Basic phenomena. Pflügers Arch 393:179–189Google Scholar
  6. 6.
    Froemter E, Gebler B (1977) Electrical properties of amphibian urinary bladded epithelia: III. The cell membrane resistances and the effect of amiloride. Pflügers Arch 371:99–108Google Scholar
  7. 7.
    Grasset E, Gunter-Smith P, Schultz SG (1983) Effects of Na-coupled alanine transport on intracellular K activities and the K conductance of the basolateral membranes ofNecturus small intestine. J Membr Biol 71:89–94Google Scholar
  8. 8.
    Guggino WB, Windhager EE, Boulpaep EL, Giebisch G (1982) Cellular and paracellular resistances of theNecturus proximal tubule. J Membr Biol 67:143–154Google Scholar
  9. 9.
    Gunter-Smith PJ, Grasset, E, Schultz SG (1982) Sodium-coupled amino acid and sugar transport byNecturus small intestine. J Membr Biol 66:25–39Google Scholar
  10. 10.
    Helman SI, Nagel W, Fisher RS (1979) Ouabain on active transepithelial sodium transport in frog skin. J Gen Physiol 74:105–127Google Scholar
  11. 11.
    Helman SI, Thompson SM (1982) Interpretation and use of electrical equivalent circuits in studies of epithelial tissues Am J Physiol 243:F519–531Google Scholar
  12. 12.
    Hoshi T, Sudo K, Suzuki Y (1976) Characteristics of changes in the intracellular potential associated with transport of neutral, dibasic and acidic amino acids inTriturus proximal tubule. Biochim Biophys Acta 448:492–504Google Scholar
  13. 13.
    Lang F, Messner G, Wang W, Oberleithner H (1983) Interaction of intracellular electrolytes and tubular transport. Klin Wochenschr 61:1029–1037Google Scholar
  14. 14.
    Lang F, Messner G, Wang W, Paulmichl M, Oberleithner H, Deetjen P (1984) The influence of intracellular sodium activity on the transport of glucose in proximal tubule of frog kidney. Pflügers Arch 401:14–21Google Scholar
  15. 15.
    Loewenstein WR (1981) Junctional intercellular communication: The cell-to-cell membrane channel. Physiol Rev 61:829–913Google Scholar
  16. 16.
    Matsumura Y, Cohen B, Guggino WB, Giebisch G (1984) Regulation of the basolateral potassium conductance of theNecturus proximal tubule. J Membr Biol 79:153–161Google Scholar
  17. 17.
    Messner G, Oberleithner H, Lang F (1985) The effect of phenylalanine on the electrical properties of proximal tubule cells in the frog kidney. Pflügers Arch 404:138–144Google Scholar
  18. 18.
    Messner G, Wang W, Paulmichl M, Oberleithner H, Lang F (1985) Ouabain decreases apparent potassium-conductance in proximal tubules of the amphibian kidney. Pflügers Arch 404:131–137Google Scholar
  19. 19.
    Petersen OH, Maruyama Y (1984) Calcium-activated potassium channels and their role in secretion. Nature 307:693–696Google Scholar
  20. 20.
    Schultz SG (1981) Homocellular regulatory mechanisms on sodium transporting epithelia: avoidance of extinction by “flush-through”. Am J Physiol 241:F579-F590Google Scholar
  21. 21.
    Schwarz W, Passow H (1983) Ca2+ activated K+ channels in erythrocytes and excitable cells. Ann Rev Physiol 45:359–374Google Scholar
  22. 22.
    Voelkl H, Greger R (1985) Effects of phlorrhizin and temperature changes on basolateral membrane potential in isolated in vitro perfused proximal tubules of mouse kidney. Pflügers Arch 403:R15Google Scholar
  23. 23.
    Wang W, Messner G, Oberleithner H, Lang F, Deetjen P (1984) The effect of ouabain on intracellular activities of K+, Na+, Cl, H+ and Ca2+ in proximal tubules of frog kidneys. Pflügers Arch 401:6–13Google Scholar

Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • G. Messner
    • 1
  • G. Stulnig
    • 1
  • W. Rehwald
    • 1
  • F. Lang
    • 1
  1. 1.Institutes of Physiology and Medical PhysicsUniversity of InnsbruckInnsbruckAustria

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