Pflügers Archiv

, Volume 416, Issue 5, pp 533–539

Madin-Darby canine kidney cells

II. Aldosterone stimulates Na+/H+ and Cl/HCO3 exchange
  • H. Oberleithner
  • U. Vogel
  • U. Kersting
  • W. Steigner
Transport Processes, Metabolism and Endocrinology; Kidney, Gastrointestinal Tract, and Exocrine Glands

DOI: 10.1007/BF00382686

Cite this article as:
Oberleithner, H., Vogel, U., Kersting, U. et al. Pflügers Arch. (1990) 416: 533. doi:10.1007/BF00382686

Abstract

Experiments in dome epithelium of Madin-Darby canine kidney (MDCK) cells were performed to elucidate aldosterone action on acid-base transport. By means of pH-sensitive microelectrodes the pH of the dome fluid was measured while the apical plasma membrane was superfused. In the absence of HCO3the dome fluid (facing the basolateral cell membrane) alkalinized in response to 10−7 mol/l aldosterone. Amiloride (10−3 mol/l) inhibited dome formation and pH recovery of the dome fluid from an extracellular acid load. In the presence of HCO3dome fluid acidified in response to aldosterone. The stilbene derivative diisothiocyanate-stilbene-2,2′-disulphonic acid (DIDS) or removal of Cl from the apical perfusate inhibited this dome acidification. In aldosterone-depleted MDCK monolayers HCO3was actively accumulated in the dome fluid in contrast to aldosterone-supplemented cells. The results indicate that aldosterone stimulates both amiloride-sensitive Na+/H+ exchange and DIDS-sensitive Cl/HCO3exchange in the apical cell membrane of MDCK cells. In the absence of aldosterone the HCO3extrusion process is localized in the basolateral membrane in series with apical Na+/H+ exchange, while in the presence of aldosterone Cl/HCO3is mainly localized in the apical membrane in parallel with Na+/H+ exchange. Cl exits the cell through apical Cl channels and is absorbed via the paracellular route.

Key words

MDCK-cells Aldosterone Na+/H+ exchange Cl/HCO3exchange Intercalated cells 

Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • H. Oberleithner
    • 1
  • U. Vogel
    • 1
  • U. Kersting
    • 1
  • W. Steigner
    • 1
  1. 1.Department of PhysiologyUniversity of WürzburgWürzburgGermany