Summary
Electrophysiologic and tracer experiments have shown that Cl− entersNecturus proximal tubule cells from the tubule lumen by a process coupled to the flow of Na+, and that Cl− entry is electrically silent. The mechanism of Cl− exit from the cell across the basolateral membrane has not been directly studied. To evaluate the importance of the movement of Cl− ions across the basolateral membrane, the relative conductance of Cl− to K+ was determined by a new method. Single-barrel ion-selective microelectrodes were used to measure intracellular Cl− and K+ as a function of basolateral membrane PD as it varied normally from tubule to tubule. Basolateral membrane Cl− conductance was about 10% of K+ conductance by this method. A second approach was to voltage clamp the basolateral PD to 20 mV above and below the spontaneous PD, while sensing intracellular Cl− activity with the second barrel of a double-barrel microelectrode. An axial wire electrode in the tubule lumen was used to pass current across the tubular wall and thereby vary the basolateral membrane PD. Cell Cl− activity was virtually unaffected by the PD changes. We conclude that Cl− leavesNecturus proximal tubule cells by a neutral mechanism, possibly coupled to the efflux of Na+ or K+.
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References
Anagnostopoulos, T. 1973. Biionic potentials in the proximal tubule ofNecturus kidney.J. Physiol. (London) 233(2):375
Anagnostopoulos, T., Planelles, G. 1979. Organic anion permeation at the proximal tubule ofNecturus.Pfluegers Arch. 381:231
Anagnostopoulos, T., Velu, E. 1974. Electrical resistance of cell membranes inNecturus kidney.Pfluegers Arch. 346:327
Boulpaep, E.L. 1967. Ion permeability of the peritubular and luminal membrane of the renal tubular cell.In: Transport und Funktion Intracellulärer Electrolyte. F. Krück, editor, pp. 98–107. Urban & Schwarzenberg, Munich
Boulpaep, E.L. 1976a. Electrical phenomena in the nephron.Kidney Int. 9:88
Boulpaep, E.L. 1976b. Recent advances in electrophysiology of the nephron.Annu. Rev. Physiol. 38:20
Giebisch, G. 1961. Measurements of electrical potential differences on single nephrons of the perfusedNecturus kidney.J. Gen. Physiol. 44:659
Khuri, R.N., Agulian, S., Bogharian, K., Aklanjian, D. 1975. Electrochemical potentials of chloride in proximal renal tubule ofNecturus maculosus.Comp. Biochem. Physiol. 50A:695
Khuri, R.N., Hajjar, J.J., Agulian, S., Bogharian, K., Kalloghlian, A., Bizri, H. 1972. Intracellular potassium in cells of the proximal tubule ofNecturus maculosis.Pfluegers Arch. 338:73
Kimura, G., Spring, K.R. 1978. Transcellular and paracellular trace chloride fluxes inNecturus proximal tubule.Am. J. Physiol. 235(6):F617 orAm. J. Physiol.: Renal Fluid Electrolyte Physiol.4(6):F617
Kimura, G., Spring, K.R. 1979. Luminal Na+ entry intoNecturus proximal tubule cells.Am. J. Physiol. 236(3):F295 orAm. J. Physiol: Renal Fluid Electrolyte Physiol.5(3):F295
Kimura, G., Spring, K.R. 1980. Ionic conductance of the cell membranes and shunts ofNecturus proximal tubule.Curr. Topics Membr. Transp. 13:265
Ogden, T.E., Citron, M.C., Pierantoni, R. 1978. The jetstream microbeveller: An inexpensive way to bevel ultrafine glass micropipettes.Science. 201:469
Reuss, L. 1979. Electrical properties of the cellular transepithelial pathway inNecturus gallbladder. III. Ionic permeability of the basolateral cell membrane.J. Membrane Biol. 47:239
Reuss, L., Weinman, S.A. 1979. Intracellular ionic activities and transmembrane electrochemical potential differences in gall-bladder epithelium.J. Membrane Biol. 49:345
Spring, K.R., Giebisch, G. 1977. Tracer Na fluxes inNecturus proximal tubule.Am. J. Physiol. 232:F461 orAm. J. Physiol.: Renal Fluid.Electrolyte Physiol. 1:F461
Spring, K.R., Kimura, G. 1978. Chloride reabsorption by renal proximal tubules ofNecturus.J. Membrane Biol. 38:233
Spring, K.R., Paganelli, C.V. 1972. Sodium flux inNecturus proximal tubule under voltage clamp.J. Gen. Physiol. 60:181
Whittembury, G., Diezi, F., Diezi, J., Spring, K., Giebisch, G. 1975. Some aspects of proximal tubular sodium chloride reabsorption inNecturus kidney.Kidney Int. 7:293
Windhager, E.E., Boulpaep, E.L., Giebisch, G. 1966. Electrophysiological studies on single nephrons.Proc. Int. Congr. Nephrol. (3rd, Washington, D.C.)1:35
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Shindo, T., Spring, K.R. Chloride movement across the basolateral membrane of proximal tubule cells. J. Membrain Biol. 58, 35–42 (1981). https://doi.org/10.1007/BF01871032
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DOI: https://doi.org/10.1007/BF01871032