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. 1989 May;412:365–374. doi: 10.1113/jphysiol.1989.sp017621

A near-zero membrane potential in transporting corneal endothelial cells of rabbit.

S Hodson 1, C Wigham 1
PMCID: PMC1190581  PMID: 2600836

Abstract

1. When rabbit corneal endothelial cells are impaled with 3 M-KCl-filled microelectrodes (Rt = 20-70 M omega) a stable membrane potential of -28.7 +/- 4.8 mV (mean +/- S.D., n = 400) is measured. 2. Varying the [KCl] of the filling solution causes a change in measured membrane potential; 154 mM gives typically -2 mV, 10 mM typically +37 mV. 3. Variation in membrane potential with different [KCl] cannot be ascribed to tip potential. Double-barrelled microelectrodes containing a different [KCl] in each barrel both give the same membrane potential when inserted into a cell. 4. Microelectrodes filled with a reference liquid ion exchanger (RLIE) give a membrane potential of +2 mV. 5. Impaling a cell with a double-barrelled microelectrode, one barrel containing KCl and the other RLIE, showed that the ion exchanger is not having a toxic effect on the cell and does not affect membrane potential measured by the KCl-filled barrel. 6. We suggest that microelectrodes containing non-isotonic concentrations of KCl generate a significant and artifactual change in membrane potential of corneal endothelial cells caused by the movement of excess KCl (originating from the microelectrode tip) across the plasma membrane where a liquid-junction potential is generated. 7. We further suggest that the physiological membrane potential of corneal endothelial cells is around zero. This could result from a solution of the constant field equation where: 0.9 PNa congruent to PK congruent to 3.2 PCl.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. ADRIAN R. H. The effect of internal and external potassium concentration on the membrane potential of frog muscle. J Physiol. 1956 Sep 27;133(3):631–658. doi: 10.1113/jphysiol.1956.sp005615. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Geisler C. D., Lightfoot E. N., Schmidt F. P., Sy F. Diffusion effects of liquid-filled micropipettes: a pseudobinary analysis of electrolyte leakage. IEEE Trans Biomed Eng. 1972 Sep;19(5):372–375. doi: 10.1109/TBME.1972.324141. [DOI] [PubMed] [Google Scholar]
  3. Hodson S. A., Wigham C. G. Paracellular ionic and transcellular water diffusions across rabbit corneal endothelium. J Physiol. 1987 Apr;385:89–96. doi: 10.1113/jphysiol.1987.sp016485. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Hodson S., Miller F. The bicarbonate ion pump in the endothelium which regulates the hydration of rabbit cornea. J Physiol. 1976 Dec;263(3):563–577. doi: 10.1113/jphysiol.1976.sp011645. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Hodson S. Observations on the posterior membrane of the corneal endothelium. Exp Eye Res. 1969 Apr;8(2):99–101. doi: 10.1016/s0014-4835(69)80018-7. [DOI] [PubMed] [Google Scholar]
  6. Jentsch T. J., Matthes H., Keller S. K., Wiederholt M. Anion dependence of electrical effects of bicarbonate and sodium on cultured bovine corneal endothelial cells. Pflugers Arch. 1985 Feb;403(2):175–185. doi: 10.1007/BF00584097. [DOI] [PubMed] [Google Scholar]
  7. Lim J. J., Fischbarg J. Intra-cellular potential of rabbit corneal endothelial cells. Exp Eye Res. 1979 Jun;28(6):619–626. doi: 10.1016/0014-4835(79)90063-0. [DOI] [PubMed] [Google Scholar]
  8. Oxford G. S., Swenson R. P. n-Alkanols potentiate sodium channel inactivation in squid giant axons. Biophys J. 1979 Jun;26(3):585–590. doi: 10.1016/S0006-3495(79)85273-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Thomas R. C., Cohen C. J. A liquid ion-exchanger alternative to KCl for filling intracellular reference microelectrodes. Pflugers Arch. 1981 Apr;390(1):96–98. doi: 10.1007/BF00582719. [DOI] [PubMed] [Google Scholar]
  10. Tsien R. Y., Rink T. J. Neutral carrier ion-selective microelectrodes for measurement of intracellular free calcium. Biochim Biophys Acta. 1980 Jul;599(2):623–638. doi: 10.1016/0005-2736(80)90205-9. [DOI] [PubMed] [Google Scholar]
  11. Wiederholt M., Koch M. Intracellular potentials of isolated rabbit and human corneal endothelium. Exp Eye Res. 1978 Nov;27(5):511–518. doi: 10.1016/0014-4835(78)90136-7. [DOI] [PubMed] [Google Scholar]
  12. Wigham C., Hodson S. The movement of sodium across short-circuited rabbit corneal endothelium. Curr Eye Res. 1985 Dec;4(12):1241–1245. doi: 10.3109/02713688509017682. [DOI] [PubMed] [Google Scholar]

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