Pflügers Archiv

, Volume 407, Supplement 2, pp S116–S122 | Cite as

Single apical membrane anion channels in primary cultures of canine tracheal epithelium

  • Michael J. Welsh
Conductive Pathways


To investigate the cellular mechanism responsible for the apical membrane Cl conductance in airway epithelia, we used the patch-clamp technique to study single ion channels in primary cultures of canine tracheal epithelium. The cells contained an anion channel that had a single channel conductance of approximately 29 pS at negative voltages in symmetrical 145 mmol/l Cl solutions. In symmetrical Cl solutions the excised single-channel current-voltage relation was nonlinear, with conductance increasing at depolarizing voltages. The channel was inhibited by diphenylamine-2-carboxylate and anthracene-9-carboxylic acid at concentrations similar to those required to inhibit transepithelial Cl secretion. The channel was found in freshly isolated cells, isolated cells in culture, and in the apical membrane of confluent areas of cells. When attached to the cell the channel was activated by addition of isoproterenol in some, but not all cases. Often it was not observed to open until the patch was excised from the cell. The channel was not strongly voltage-gated, nor was it acutely regulated by internal Ca in the excised, inside-out configuration. These results suggest that this channel may be responsible for the apical Cl conductance in canine tracheal epithelium.

Key words

Chloride channels Patch-clamp Airway epithelium Chloride secretion Cultured epithelial cells Cystic fibrosis 


  1. 1.
    Al-Bazzaz FJ (1981) Role of cyclic AMP in regulation of chloride secretion by canine tracheal mucosa. Am Rev Respir Dis 123:295–298Google Scholar
  2. 2.
    Al-Bazzaz FJ, Cheng E (1979) Effect of catecholamines on ion transport in dog tracheal epithelium. J Appl Physiol 47:397–403Google Scholar
  3. 3.
    Al-Bazzaz FJ, Jayaram T (1981) Ion transport by canine tracheal mucosa: Effect of elevation of cellular calcium. Exp Lung Res 2:121–130Google Scholar
  4. 4.
    Blatz AI, Magleby KI (1983)Single voltage-dependent chloride selective channels of large conductance in cultured rat muscle. Biophys J 43:237–241Google Scholar
  5. 5.
    Coleman DL, Tuet IK, Widdicombe JH (1984) Electrical properties of dog tracheal epithelial cells grown in monolayer culture. Am J Physiol 246:C355-C359Google Scholar
  6. 6.
    Colombini M (1979) A candidate for the permeability pathway of the outer mitochondrial membrane. Nature 279:643–645Google Scholar
  7. 7.
    DiStefano A, Wittner M, Schlatter E, Lang HJ, Englert H, Greger R (1985) Diphenylamine-2-carboxylate, a blocker of the Cl-conductive pathway in Cl-transporting epithelia. Pflügers Arch 405:S95-S100Google Scholar
  8. 8.
    Gray R, Johnston D (1985) Rectification of single GABA-gated chloride channels in adult hippocampal neurons. J Neurophysiol 54:134–141Google Scholar
  9. 9.
    Greger R, Schlatter E, Gögelein H (1985) Cl-channels in the apical cell membrane of the rectal gland “induced” by cAMP. Pflügers Arch 403:446–448Google Scholar
  10. 10.
    Greger R, Schlatter E, Wang F, Forrest JN Jr (1984) Mechanism of NaCl secretion in rectal gland tubules of spiny dogfish (Squalus acanthias). Pflügers Arch 402:376–384Google Scholar
  11. 11.
    Hamill OP, Marty A, Neher E, Sakmann B, Sigworth FJ (1981) Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflügers Arch 391:85–100Google Scholar
  12. 12.
    Hamill OP, Bormann J, Sakmann B (1983) Activation of multiple conductance state chloride channels in spinal neurones by glycine and GABA. Nature 305:805–808Google Scholar
  13. 13.
    Hanrahan JW, Alles WP, Lewis SA (1984) A voltage gated Cl channel in cultured mammalian urinary bladder epithelium: a patch clamp study. Biophys J 45:300aGoogle Scholar
  14. 14.
    Hanrahan JW, Alles WP, Lewis SA (1985) Single anion-selective channels in basolateral membrane of a mammalian tight epithelium. Proc Natl Acad Sci USA 82:7791–7795Google Scholar
  15. 15.
    Heintze K, Stewart CP, Frizzell RA (1983) Sodium-dependent chloride secretion across rabbit descending colon. Am J Physiol 244:G357-G365Google Scholar
  16. 16.
    Kolb HA, Brown CDA, Murer H (1985) Identification of a voltage-dependent anion channel in the apical membrane of a Cl secretory epithelium (MDCK). Pflügers Arch 403:262–265Google Scholar
  17. 17.
    Miller C, White M (1984) Dimeric structure of single chloride channels fromTorpedo electroplax. Proc Natl Acad Sci USA 81:2772–2775Google Scholar
  18. 18.
    Nagel W, Reinach P (1980) Mechanism of stimulation by epinephrine of active transepithelial Cl transport in isolated frog cornea. J Membr Biol 56:73–79Google Scholar
  19. 19.
    Nelson DJ, Tang JM, Palmer LG (1984) Single-channel recordings of apical membrane chloride conductance in A6 epithelial cells. J Membr Biol 80:81–89Google Scholar
  20. 20.
    Schneider GT, Cook DI, Gage PW, Young JA (1985) Voltage sensitive, high-conductance chloride channel in the luminal membrane of cultured pulmonary alveolar (type II) cells. Pflügers Arch 404:354–357Google Scholar
  21. 21.
    Shoemaker R, Frizzel R, Dwyer TM, Farley JM (1985) Characteristics of Cl channels in primary cultures of dog tracheal epithelial cells. Fed Proc 44:647Google Scholar
  22. 22.
    Shorofsky SR, Field M, Fozzard HA (1983) Electrophysiology of Cl secretion in canine trachea. J Membr Biol 72:105–115Google Scholar
  23. 23.
    Shorofsky SR, Field M, Fozzard HA (1984) Mechanism of Cl secretion in canine trachea: changes in intracellular chloride activity with secretion. J Membr Biol 81:1–8Google Scholar
  24. 24.
    Smith PL, Welsh MJ, Stoff JS, Frizzell RA (1982) Chloride secretion by canine tracheal epithelium. I. Role of intracellular cAMP levels. J Membr Biol 70:217–226Google Scholar
  25. 25.
    Welsh MJ (1983) Intracellular chloride activities in canine tracheal epithelium. Direct evidence for sodium-coupled intracellular chloride accumulation in a chloride-secreting epithelium. J Clin Invest 71:1392–1402Google Scholar
  26. 26.
    Welsh MJ (1984) Anthracene-9-carboxylic acid inhibits an apical membrane chloride conductance in canine tracheal epithelium. J Membr Biol 78:61–71Google Scholar
  27. 27.
    Welsh MJ (1984) Energetics of chloride secretion in canine tracheal epithelium. Comparison of the metabolic cost of chloride transport with the metabolic cost of sodium transport. J Clin Invest 74:262–268Google Scholar
  28. 28.
    Welsh MJ (1985) Basolateral membrane potassium conductance is independent of sodium pump activity and membrane voltage in canine tracheal epithelium. J Membr Biol 84:25–33Google Scholar
  29. 29.
    Welsh MJ (1985) Ion transport by primary cultures of canine tracheal epithelium: Methodology, morphology and electrophysiology. J Membr Biol 88:149–163Google Scholar
  30. 30.
    Welsh MJ (1986) Adrenergic regulation of ion transport by primary cultures of canine tracheal epithelium. I. Cellular electrophysiology. J Membr Biol 91:121–128Google Scholar
  31. 31.
    Welsh MJ, McCann JD (1985) Intracellular calcium regulates basolateral potassium channels in a chloride secreting epithelium. Proc Natl Acad Sci USA 82:8823–8826Google Scholar
  32. 32.
    Welsh MJ, Smith PL, Frizzell RA (1982) Chloride secretion by canine tracheal epithelium. II. The cellular electrical potential profile. J Membr Biol 70:227–238Google Scholar
  33. 33.
    Welsh MJ, Smith PL, Frizzell RA (1983) Chloride secretion by canine tracheal epithelium. III. Membrane resistances and electromotive forces. J Membr Biol 71:209–218Google Scholar
  34. 34.
    Widdicombe JH, Welsh MJ, Finkbeiner WE (1985) Cystic fibrosis decreases the apical membrane chloride permeability of monolayers cultured from cells of tracheal epithelium. Proc Natl Acad Sci USA 82:6167–6171Google Scholar

Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • Michael J. Welsh
    • 1
  1. 1.Laboratory of Epithelial Transport, Pulmonary Division, Department of Internal MedicineUniversity of Iowa College of MedicineIowa CityUSA

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