It is well recognized that DADLE may be protective against ischemia in a variety of organs other than the heart.
Comparison of the number of pigs with sustained ventricular tachycardia and the average QT dispersion (QTdisp) and the average percentage increase over control baseline values of QTdisp in control and DADLE infused pigs during coronary occlusion.
Nonetheless, it is important to note that the average DP/dt (an indicator of contractility) fell significantly during the occlusion and infusion period for the Cpigs (-20%) while it remained stable for the Dpigs receiving DADLE during this same period.
A 20-gauge needle was placed into the lumen of the LAD immediately distal to the occlusion, and 10 ml heparinized whole blood, with (Dpigs) or without (Cpigs) DADLE (Peninsula Laboratories Inc.
In a total of 12 pigs studied (6 Dpigs; 6 Cpigs), 83% of the Dpigs (5 out of 6) and 17% of the Cpigs (1 out of 6) there developed a sustained ventricular tachyarrhythmias within 5 minutes after the infusion of DADLE or sham control into the localized segment of myocardium (Table 1).
DADLE is a [delta]-opioid receptor agonist that has been extensively studied with regard to its effect on myocardial cell function and has been used as a tool to investigate the mechanisms of IP (2,5).