Beta-adrenergic receptors and intracellular signalling pathway in stunned and non-ischemic regions of pig myocardium

Basic Res Cardiol. 2001 Jul;96(4):388-94. doi: 10.1007/s003950170047.

Abstract

The beta-adrenergic pathway may have a role in the pathophysiology of ischemic syndromes characterised by reversible left ventricular dysfunction, such as myocardial stunning and other clinical conditions of unstable angina or coronary spasms, or chronic reversible left ventricular dysfunction, which might be a consequence of repeated events of short-term ischemia ("repetitive stunning"). A partial-to-total occlusion of the left anterior descending coronary artery in pigs was used to induce short periods of ischemia (total ischemic time 12 +/- 2 min). Hypokinesis and dyskinesis of the myocardium were considered signs of myocardial dysfunction. We found a maintained function of the beta-adrenergic signalling system. Density and affinity of beta-adrenergic receptors were not different in stunned and non-ischemic regions, nor were cyclic AMP and cyclic GMP intracellular contents and ratio, nor well as the ratio of stimulatory/inhibitory G protein a subunits. Our findings are in agreement with a maintained beta-adrenergic signalling system in the pathophysiology of chronic reversible left ventricular dysfunction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cyclic AMP / metabolism
  • Cyclic GMP / metabolism
  • GTP-Binding Proteins / metabolism
  • Intracellular Membranes / physiology*
  • Myocardial Stunning*
  • Myocardium / metabolism*
  • Protein Isoforms / metabolism
  • Receptors, Adrenergic, beta / physiology*
  • Signal Transduction
  • Swine

Substances

  • Protein Isoforms
  • Receptors, Adrenergic, beta
  • Cyclic AMP
  • GTP-Binding Proteins
  • Cyclic GMP