Affinity isolation of imidazoline binding proteins from rat brain using 5-amino-efaroxan as a ligand

FEBS Lett. 1999 Mar 19;447(1):61-4. doi: 10.1016/s0014-5793(99)00264-1.


We have employed an amino derivative of the imidazoline ligand, efaroxan, to isolate imidazoline binding proteins from solubilised extracts of rat brain, by affinity chromatography. A number of proteins were specifically retained on the affinity column and one of these was immunoreactive with an antiserum raised against the ion conducting pore component of the ATP-sensitive potassium channel. Patch clamp experiments confirmed that, like its parent compound, amino-efaroxan blocks ATP-sensitive potassium channels in human pancreatic beta-cells and can stimulate the insulin secretion from these cells. The results reveal that a member of the ion conducting pore component family is strongly associated with imidazoline binding proteins in brain and in the endocrine pancreas.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters*
  • Animals
  • Benzofurans / chemistry
  • Benzofurans / metabolism*
  • Benzofurans / pharmacology
  • Brain Chemistry*
  • Chromatography, Affinity / methods*
  • Humans
  • Imidazoles / chemistry
  • Imidazoles / metabolism*
  • Imidazoles / pharmacology
  • Insulin / metabolism
  • Insulin Secretion
  • Islets of Langerhans / cytology
  • Islets of Langerhans / metabolism
  • Ligands
  • Nerve Tissue Proteins / isolation & purification*
  • Nerve Tissue Proteins / metabolism
  • Patch-Clamp Techniques
  • Potassium Channels / metabolism*
  • Potassium Channels, Inwardly Rectifying*
  • Protein Binding
  • Rats
  • Receptors, Drug / metabolism
  • Sulfonylurea Receptors


  • ATP-Binding Cassette Transporters
  • Benzofurans
  • Imidazoles
  • Insulin
  • KU 08C
  • Ligands
  • Nerve Tissue Proteins
  • Potassium Channels
  • Potassium Channels, Inwardly Rectifying
  • Receptors, Drug
  • Sulfonylurea Receptors