In vivo protective effects of urocortin on ischemia-reperfusion injury in rat heart via free radical mechanisms

The aim of this study was to investigate the effects of urocortin (UCN) on oxidative stress and the mechanisms of urocortin on ischemia–reperfusion injury in vivo in the rat model. Thirty-six Sprague–Dawley rats were divided into 6 groups, including sham, control (normal saline solution), UCN1, UCN2, UCN3, and verapamil groups. The left anterior descending coronary artery of all rats except those in the sham group was treated with a 30-min occlusion followed by a 60-min reperfusion. Just before the occlusion, normal saline solution, UCN (5, 10, and 20 µg/kg body mass), or verapamil (1 mg/kg body mass) was administered. Heart rates, beating rhythm, and S-T segments were constantly monitored using an ECG. At the completion of the drug adminstration, blood samples were taken to measure the activity of superoxide dismutase (SOD), malonaldehyde (MDA), glutathione peroxidase (GSH-PX), and nitric oxide (NO) to evaluate the effects of UCN on oxidative stress. Finally, the size of infarction was measured. Arrhythm...