Immunolocalization of an inwardly rectifying K+ channel, K(AB)-2 (Kir4.1), in the basolateral membrane of renal distal tubular epithelia

FEBS Lett. 1996 Jun 10;388(1):11-5. doi: 10.1016/0014-5793(96)00502-9.


Immunolocalization of K(AB)-2 (Kir4.1), an inwardly rectifying K+ channel with a putative ATP-binding domain, was examined in rat kidney where expression of K(AB)-2 mRNA was previously shown. Anti-K(AB)-2 antibody was raised in rabbit and then affinity-purified. An immunohistochemical study revealed that K(AB)-2 immunoreactivity was detected specifically in the basolateral membrane of distal tubular epithelia. Therefore, K(AB)-2 is the first K+ channel shown to be localized in the basolateral membrane of renal epithelia. The finding suggests that K(AB)-2 may contribute to supplying K+ to the Na(+)-K+ pump, which is abundant in the basolateral membrane of distal tubular epithelia, as well as to maintenance of the deep negative membrane potential of these cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibody Specificity
  • Cell Membrane / chemistry
  • Epithelium / chemistry
  • Kidney Cortex / chemistry
  • Kidney Tubules, Distal / chemistry*
  • Male
  • Molecular Sequence Data
  • Oligopeptides / chemical synthesis
  • Oligopeptides / immunology
  • Potassium Channels / analysis*
  • Potassium Channels, Inwardly Rectifying*
  • Rabbits
  • Rats
  • Rats, Wistar


  • Oligopeptides
  • Potassium Channels
  • Potassium Channels, Inwardly Rectifying