Korean J Phys Anthropol.  1998 Dec;11(2):327-347.

Effects of Ischemic Preconditioning,Adenosine and Pinacidil on the Changes in Immunoreactivities of Cu,Zn - and Mn - SOD in the Rectus Femoris Muscles of the Rats after Ischemia and Timely Reperfusion

• Paik DJ
• Kim BC

Abstract

A brief episode of ischemia and reperfusion termed 'ischemic preconditioning' has been established as rendering muscle tolerance to damage during a subsequent prolonged ischemia. The effects of ischemic preconditioning in the cardiac muscle is related to the stimulation of adenosine A1 receptor and the opening of KATP channel. The effect and mechanism of ischemic preconditioning in the skeletal muscle is not known clearly. The author performed the present study to investigate the effect and the mechanisms of ischemic preconditioning by measuring the SOD immunoreactivities on timely reperfused ischemic muscles. The healthy Sprague -Dawley rats weighing from 200 g to 250 g were used as experimental animals. Under pentobarbital (50 mg/kg) anesthesia, lower abdominal incision was done and left common iliac artery was ligated by using vascular clamp for 2 hours. Rectus femoris muscles were obtained at 0 hour, 1 hour, 2 hours, 6 hours, 12 hours, 24 hours, 48 hours and 72 hours of reperfusion. The group of ischemic preconditioning underwent three episodes of 5 minute occlusion and 5 minute reperfusion of common iliac artery followed by 2 hours of ischemia and timely reperfusion. Adenosine (50 microgram/kg) or pinacidil (1 mg/kg) were administered intravenously before ischemia and 2 hours of ischemia and timely reperfusion was done. 10 microM thick cryosections in all groups were obtained. The immunoreactivities of SOD were observed by use of antihuman Cu,Zn -and Mn -SOD antibodies. The results obtained were as follows. 1. The immunoreactivities of SOD in the rectus femoris muscles of rats increased after ischemic preconditioning. The patterns of the changes in immunoreactivities of Cu, Zn -and Mn -SOD were similar at the muscle fibers with large section area or small section area. 2. After the treatment of adenosine, the immunoreactivities of Cu, Zn -SOD in the group of 2 hours and 24 hours reperfusion and the immunoreactivities of Mn -SOD in the group of 24 hours reperfusion increased. After the treatment of pinacidil, the immunoreactivities of Mn - SOD increased and the immunoreactivities of Cu, Zn -SOD are similar to normal control rat. 3. After 2 hours of ischemia the immunoreactivities of SOD were similar to normal control rat. The immunoreactivities of Cu, Zn -SOD in the group of 1 hour, 2 hours and 24 hours reperfusion and those of Mn -SOD in all groups of reperfusion increased. 4. In the group of 2 hours ischemia and timely reperfusion with ischemic preconditioning, the immunoreactivities of SOD in the muscle fiber with large section area decreased and those of SOD in the muscle fibers with small section area increased in comparison with the group of 2 hours and timely reperfusion. The pattern of change between immunoreactivities of Cu,Zn -and Mn -SOD in each muscle fiber were similar. 5. After the treatment of adenosine, the immunoreactivities of SOD increased in the group of 1 hour, 2 hours, 6 hours and 12 hours reperfusion. After the treatment of pinacidil, the immunoreactivities of SOD increased in the group of 1 hour, 2 hours, 6 hours, 12 hours and 24 hours reperfusion. Consequently, these results suggest that the immunoreactivities of SOD increase after 2 hours of ischemia and timely reperfusion with ischemic preconditioning. The effect of ischemic preconditioning is related to opening of KATP channel partly.

MeSH Terms

Adenosine
Anesthesia
Animals
Antibodies
Iliac Artery
Ischemia*
Ischemic Preconditioning
Muscle, Skeletal
Muscles*
Myocardium
Pentobarbital
Pinacidil*
Quadriceps Muscle*
Rats*
Receptor, Adenosine A1
Reperfusion*
Adenosine
Antibodies
Pentobarbital
Pinacidil
Receptor, Adenosine A1