Rat inwardly rectifying potassium channel Kir6.2: cloning electrophysiological characterization, and decreased expression in pancreatic islets of male Zucker diabetic fatty rats

Biochem Biophys Res Commun. 1996 Mar 27;220(3):532-8. doi: 10.1006/bbrc.1996.0439.


The ATP-sensitive potassium channel of insulin-secreting pancreatic beta-cells is a complex of Kir6.2, a member of the inwardly rectifying potassium channel superfamily, and the sulfonylurea receptor. We have isolated cDNA clones encoding rat Kir6.2. Co-expression of rat Kir6.2 and sulfonylurea receptor in human embryonic kidney cells generated a potassium current with the properties of the beta-cell ATP-sensitive potassium channel. A quantitative reverse transcriptase-polymerase chain reaction assay indicated that Kir6.2 and sulfonylurea receptor mRNAs were abundantly expressed in rat islets and that expression of Kir6.2 mRNA was reduced by >70% in islets from Zucker diabetic fatty male rats, whereas there was no significant change in sulfonylurea receptor mRNA levels. Thus, decreased expression of Kir6.2 could contribute to the beta-cell dysfunction which characterizes diabetes mellitus in this animal model.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenosine Triphosphate / pharmacology
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cattle
  • Cell Line
  • Cloning, Molecular
  • DNA Primers
  • Diabetes Mellitus / genetics
  • Diabetes Mellitus / physiopathology*
  • Diabetes Mellitus, Type 2 / genetics
  • Diabetes Mellitus, Type 2 / physiopathology*
  • Gene Expression*
  • Glyburide / pharmacology
  • Humans
  • Islets of Langerhans / metabolism*
  • Islets of Langerhans / physiopathology
  • Male
  • Membrane Potentials / drug effects
  • Molecular Sequence Data
  • Obesity*
  • Organ Specificity
  • Polymerase Chain Reaction
  • Potassium Channels / biosynthesis
  • Potassium Channels / physiology*
  • Potassium Channels, Inwardly Rectifying*
  • RNA, Messenger / analysis
  • RNA, Messenger / biosynthesis
  • Rats
  • Rats, Zucker
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / metabolism
  • Reference Values
  • Sequence Homology, Amino Acid


  • DNA Primers
  • Potassium Channels
  • Potassium Channels, Inwardly Rectifying
  • RNA, Messenger
  • Recombinant Proteins
  • Adenosine Triphosphate
  • Glyburide

Associated data

  • GENBANK/U44897