A comparison of efficacy between conventional and modified methods of the chronic myocardial ischemia/reperfusion model

The objective of this study is to develop and compare the efficacy of a modified versus conventional rat model of chronic myocardial ischemia/reperfusion. Sixty Sprague Dawley (SD) rats were randomly divided into two groups, a modified group (mask respiratory support and short-time chest-opening) and a conventional group (tracheal intubation and long-time chest-opening). Operation time, surgical success rate, survival rate and infarct size were investigated. In addition, the post-operative living state of the rats was observed. In the perioperative period, the surgical success rate was greater in the modified model (P < 0.05 vs. conventional model). Both chest-opening time and spontaneous respiration recovery time were significantly shorter in the modified group versus the conventional model (P < 0.001). Postoperative resumption of normal behaviors and activities was quicker in the modified surgical group, which demonstrated a statistically significant mortality benefit compared to the conventional group (P < 0.001). Infarct size, assessed via triphenyltetrazolium chloride staining, was without statistical difference between the 2 groups (P > 0.05). The modified method offers advantages of simplicity, efficiency and independent conduct. Its employment enhances the success rate of the chronic rat myocardial ischemia/reperfusion model.