Isolation and characterization of β1-adrenergic receptors from adult, rat cardiac myocytes

Academic Article

Abstract

  • The β-receptors were isolated from rat cardiac myocytes and characterized. Isolated myocytes were prepared from adult rat hearts and characterized for viability. Membrane proteins were solubilized from myocytes with 1% Triton X-102. The solubilized membrane proteins were fractionated by DEAE-Sephacel ion exchange column chromatography. Two major protein peaks were obtained. The second protein peak sample was found to contain β-receptors to which 125I-15-(4′-azido-3′-iodobenzyl)-carazolol (125I-ABC) {norm of matrix} was specifically bound. This sample was labeled covalently with 125I-ABC by UV. irradiation. The radiolabeled sample was applied to a Sepharose CL-6B gel column. Two radiolabeled protein peaks, one with a molecular weight of approximately 570,000 and the other with a molecular weight of approximately 95,000 were found. When the 570,000-dalton complex was subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions, it was dissociated into a component with a molecular weight of 66,000. The 95,000-dalton complex was dissociated into a 58,000-dalton component upon SDS-PAGE under reducing conditions. An excess amount of isoproterenol and propranolol decreased photolabeling of the β-receptors with 125I-ABC by 60% and 40%, respectively. © 1984 Academic Press Inc. (London) Limited.
  • Digital Object Identifier (doi)

    Author List

  • Im JH; Puckett SW; Bowdon HR; Rogers WJ; Meezan E; Kim HD; Rackley CE
  • Start Page

  • 867
  • End Page

  • 873
  • Volume

  • 16
  • Issue

  • 10