Objective: To investigate cardiac function impairment and myocardial injury in rats with intestinal ischemia-reperfusion and the protective effect of cromolyn sodium.
Methods: Thirty-two SD rats were randomized into 4 groups (n=8), namely the sham operation group, model group, 50 mg/kg cromolyn sodium group, and 25 mg/kg cromolyn sodium group. Intestinal damage was induced by clamping the superior mesenteric artery for 45 min followed by reperfusion for 60 min. Cromolyn Sodium was administrated intaperitoneally 15 min before reperfusion. The heart rate (HR), left ventricle pressure (LVSP), and the maximal/minimum rate of LVSP (+dp/dt(max), -dp/dt(max)) were sacrificed immediately before ischemia (baseline, T(0)), at 15 min (T(1)), 30 min (T(2)), 45 min (T(3)) of ischemia, and at 3 min (T(4)), 5 min (T(5)), 10 min (T(6)), 15 min (T(7)), 45 min (T(8)), 60 min (T(9)) of reperfusion. At the end of the experiment, the rats were executed and the hearts were immediately removed for observation of the pathological changes and determination of MDA contents and SOD activity.
Results: Compared with the baseline T(0), the HR, +dp/dt(max), -dp/dt(max) and the LVSP were decreased significantly at T(8) and T(9) in the model group and the two cromolyn sodium groups (P<0.05). Compared with the sham operation group, these indices were also significantly decreased at T(8) and T(9) in the model group and the two cromolyn sodium groups, but the model group had significantly lower levels for these indices at T(8) and T(9) than the two cromolyn sodium groups (P<0.05). The score of myocardial injury in the model group and the two cromolyn sodium groups were significantly higher than that of group A, and 50 mg/kg cromolyn sodium group had lower score than the model group (P<0.05). The rats in the model group had significantly higher MDA levels than those in the sham operation group and the 50 mg/kg cromolyn sodium group. SOD activities in the model group and 25 mg/kg cromolyn sodium group was lower than that in the sham operation group (P<0.05), but 50 mg/kg cromolyn sodium group had significantly higher SOD activities than the model group (P<0.05).
Conclusion: Cromolyn sodium can protect the myocardium against intestal ischemia-reperfusion injury and improve the cardiac function.