The role of endothelin-1 during ischemia-reperfusion injury.

In order to investigate the role of endothelin-1 during ischemia-reperfusion injury, 80 adult male Wistar rats were subjected to three hours of ischemia and one hour of reperfusion. Animals were evenly divided into eight groups. The rats in group 1 served as the normal control group, while the rats in group 2 received an intravenous infusion of endothelin-1 in a dosage of 0.5 ng/kg/min, group 3 in a dosage of 5 ng/kg/min, and group 4 in a dosage of 50 ng/kg/min. The rats in group 5 were infused with angiotensin II (10 ng/kg/min). The rats in group 6 received an intravenous infusion of 10,000 units of superoxide dismutase and 10,000 units of catalase. Group 7 rats were infused with endothelin-1 (50 ng/kg/min), superoxide dismutase (10,000 units), and catalase (10,000 units). Group 8 rats received an infusion of angiotensin II (10 ng/kg/min), superoxide dismutase (10,000 units) and catalase (10,000 units). The infusions were given during the reperfusion period. After one hour of reperfusion, the gastrocnemius and soleus muscles of the experimental animals were excised and assayed for ischemia-reperfusion injury by measuring triphenyltetrazolium chloride (TTC) reduction. The results showed that the limb activity of the ischemic extremity was 40.33 +/- 2.75% in group 1, 41.62 +/- 4.08% in group 2, 14.42 +/- 3.14% in group 3, 4.43 +/- 1.05% in group 4, 23.81 +/- 3.51% in group 5, 57.23 +/- 4.52% in group 6, 31.79 42- 3.63% in group 7, and 27.39 +/- 3.95% in group 8. Endothelin-1 reduced the limb activity in a dose-dependent manner.(ABSTRACT TRUNCATED AT 250 WORDS)