Figure 4.
Opioid effects on postischemic myocardial tissue perfusion. Regional myocardial perfusion of the anterior left ventricular wall was assessed using colored microsphere injections at 15 and 120 min after working mode initiation (Tw = 0). Transmural biopsies were taken from the myocardium at experiment termination and separated into three layers: (a) subendocardial, (b) midmyocardial, and (c) subepicardial. Flows were normalized per gram of tissue. Preliminary evidence of the no-reflow phenomenon was seen at the Tw = 120 time point, as all control hearts showed declining trends in flow to all layers of the heart. This trend was not present in the Deltorphin D-treated hearts and a significant increase in flow at Tw = 120 was found in the midmyocardial level. *P < 0.05 versus control