This I/R injury procedure in mice is essentially the same as the procedure for inducing MI except that a slipknot is tied around the LCA 2-3 mm from its origin with a 6-0 silk suture as shown in Fig. 2A. The heart is then quickly placed back into the thoracic space followed by manual evacuation of air and the skin closing (Fig. 2B). The internal needle end of slipknot suture is cut as short as possible and the other end of the suture is approximately 0.8 cm long and remains outside of the chest (Fig. 2C). After 30 min of ischemia, the slipknot is released by pulling the long end of slipknot suture smoothly and gently until a feeling of release is sensed at which time the myocardium begins reperfusing. This outside-the-skin suture knot releasing method should only be attempted by the experienced surgeon. Alternatively, the mouse can be re-anesthetized with 2% isoflurane inhalation, the chest reopened, and the slipknot released by pulling the long end of slipknot suture smoothly and gently, and then following manual evacuation of the pneumothorax and chest closure. As above for the MI model, ventilation is recommended until times are fast enough to do this procedure without ventilation.