Objective  To investigate the dynamic changes of and malondialdehyde content SOD and GSH-Px activity in serum and intestinal tissues in rats with abdominal injury caused by explosion.   Methods  A total of 120 male rats were divided randomly into enclosure group and free-field group

and subjected to explosion with instantaneous electric detonator. Ten uninjured rats served as normal control. Blood and intestinal tissue samples were collected immediately and at 3

8

24

48

72 h after blast injury

respectively. SOD and GSH-Px activity and malondialdehyde content in serum and intestinal tissues were measured. Additionally

a Pearson correlation analysis was carried out to determine parameter relationships.  Results  SOD and GSH-Px activity was slightly elevated within 3 h following explosive abdominal injury of rats

and then kept declining progressively (P0.05)

showing a statistically significant decrease in enclosed space as compared with open-field group (P0.05) and normal control group (P0.05). In both groups of explosion

MDA level rose continuously. MDA concentration was significantly increased within 3 h after blast injury in comparison with normal control group (P0.05). In addition

it had a statistically significant increase in enclosed group as compared with openfield group (P0.05). SOD and GSH-Px activity and MDA content in enclosed space group recovered slower within observed duration than that in free-field group (P0.05). The correlation analysis revealed a statistically significant positive correlation of MDA levels and GSH-Px activity between serum and intestinal tissues (P0.01).   Conclusion   The oxidative stress reaction occurred earlier

sustained longer and stronger in rats in enclosed space than that in open field. The observed changes in the tested parameters are attributable to oxidative stress occurrence in explosive abdominal injury. For this reason

the patients with explosive abdominal injury are recommended to receive antioxidant treatment.