Right-shifting the oxyhemoglobin dissociation curve with RSR13: effects on high-energy phosphates and myocardial recovery after low-flow ischemia

J Cardiovasc Pharmacol. 1998 Mar;31(3):359-63. doi: 10.1097/00005344-199803000-00005.


RSR13[2-(4[[(3,5-Dimethylanilino)carbonyl] methyl] phenoxy)-2-methyl propionic acid], a synthetic allosteric modifier of hemoglobin, increases O2 release from hemoglobin at low oxygen tension. The isolated blood-perfused rat heart was examined during potassium-arrest to determine the effects of RSR13 on the concentration of phosphocreatine (PCr) and adenosine triphosphate (ATP) by using 31P nuclear magnetic resonance (NMR) spectroscopy throughout an episode of low-flow ischemia. All hearts were perfused at constant flow during control (2.0 ml/min) and low-flow (0.2 ml/min) conditions. In normoxic hearts, RSR13 had no effect on either the 31P NMR spectrum or the rate-pressure product. In hearts subjected to 30 min of reduced flow, treatment with RSR13 improved mechanical function on reperfusion (p = 0.026 after 20 min; p = 0.032 after 25 min; and p = 0.045 after 30 min) at 2.0 ml/min with normokalemic blood perfusate. In potassium-arrested hearts, the rate of decrease of [ATP] was reduced in hearts exposed to RSR13 (p < or = 0.05 between 10 and 35.8 min of ischemia except at 28.4 min) during low flow. These results indicate a protective effect of RSR13 on high-energy phosphates during low-flow ischemia and mechanical recovery after reperfusion.

Publication types

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

MeSH terms

  • Aniline Compounds / pharmacology*
  • Animals
  • In Vitro Techniques
  • Magnetic Resonance Spectroscopy
  • Male
  • Myocardial Ischemia / metabolism*
  • Myocardial Ischemia / physiopathology
  • Oxyhemoglobins / drug effects*
  • Oxyhemoglobins / metabolism
  • Phosphates / metabolism*
  • Propionates / pharmacology*
  • Rats
  • Rats, Sprague-Dawley


  • Aniline Compounds
  • Oxyhemoglobins
  • Phosphates
  • Propionates
  • efaproxiral