We investigated whether intermittent restoration of blood flow just before reperfusion after ischemia could create beneficial effects similar to ischemic preconditioning, which involves intermittent stoppage of blood flow just before ischemia.Methods
Male Sprague-Dawley rats were prepared with vascular isolated cremaster muscles, then subjected to 4 hours of ischemia and 60 minutes of reperfusion. Arteriole diameters and capillary perfusion were measured by using intravital microscopy. Four groups were used: (1) untreated, (2) ischemic preconditioning (IP), (3) intermittent reperfusion (IR), and (4) ischemic preconditioning plus intermittent reperfusion (IP+IR).Results
Our results showed that IP significantly attenuated both ischemia/reperfusion-induced vasospasm and capillary no-reflow. IR was effective in attenuating vasospasm in terminal arterioles. However, IR alone was unable to significantly attenuate capillary no-reflow. Combining both IP and IR achieved the best results.Conclusion
Our results suggest both ischemic preconditioning and intermittent reperfusion are useful techniques for attenuating ischemia/reperfusion injury.