Protection of Ischemic and Reperfused Rat Heart by Aqueous Extract of Urtica Dioica

Background: Urtica dioica (U.D) has widely been used in traditional medicine for its hypotensive and vasodilatory effects. The objective of this study was to clarify the effects of aqueous extract of Urtica dioica on isolated ischemia- reperfused heart.Methods: The heart of male wistar rats were isolated and perfused according to langendorff method. In the control group (n = 13) the hearts were subjected to three steps of stabilization (30 min), normothermic global ischemia (40 min) and reperfusion (45 min). In addition, before and after ischemia, the aqueous extract of U.D (200 mg/ml) was added to perfusion solution in the test group (n=14). Different cardiac variables including left ventricular pressure, heart rate and coronary flow were measured and rate pressure product was calculated.Results: Results showed that left ventricular pressure (59.11±4.7) and rate pressure product (13680±1136) in 45th minute of reperfusion in the test group were significantly (P=0.0187 and 0.0321 respectively) greater than the control group (39.1±6.0, 9480±1480) respectively. These findings indicated decreased cardiac damage following ischemia in the test group, compared with that of control group.Conclusion: Results of the present study showed that the aqueous extract of U.D, increased the tolerance of isolated rat hearts against ischemic damage. This effect can be explained by potent antioxidant activity of the U.D extract, suggesting its clinical use in ischemic heart disease.