Benefical effect of adenosine on diastolic stunned myocardium recovery

pp. 198-203

Abstract

There ir experimental evidence that adenosine, administered only during the reperfusion period, attenuates systolic alterations of the post-ischemic ventricular dysfunction. However, it is not clear if this protection includes the diastolic dysfunction. Thus the main objective of our work was to disclose if adenosine, administered only during reperfusio, attenuates the diastolic alterations after 15 minutes of global ischemia. An additional objetive of this work was to determine the possible participation of A₁ receptors as possible mediators of the above mentioned effects. Isolated and isovolumic rabbit hears, were perfuse according to the Langerdorgg technique, and subjectede to 15 minutes the left ventricular end diastolic pressure (myocardial stiffness), adn the coronary perfusion pressure. The time constant of pressur decay during the isovolumic relaxation phase (tau, τ) was calculated. We found that adenosine administration from the beginning of the reperfusion attenuates the increase of myocardial stiffness, without modifying the early alterations of the isovolumic relaxation. This protection was mediated by activation of A₁ receptors.