AIM: To investigate the changes in plasminogen activity level during mesenteric ischemia. METHODS: We performed laparotomy in 90 female Wistar-Albino rats (average weight 230 g). In sham groups (SL) (GroupsⅠand Ⅱ) the superior mesenteric artery (SMA) and vein (SMV) were explored, but not tied. In SMA groups (Groups Ⅲ and Ⅳ) the SMA was ligated, and in SMV groups (Groups Ⅴ and Ⅵ) the SMV was ligated. On re-laparatomy 2 mL of blood was drawn at 1 h in groupsⅠ, Ⅲ and Ⅴ, and at 3 h in groups Ⅱ, Ⅳ and Ⅵ. Plasminogen levels were assessed and comparisons were made between groups and within each group. RESULTS: The mean plasminogen activity in the SL group was significantly higher than SMA (25.1 ± 10.8 vs 11.8 ± 4.6, P < 0.001) or SMV (25.1 ± 10.8 vs 13.7 ± 4.4, P < 0.001) groups both at 1 h and at 3 h (29.8 ± 8.9 vs 15.1 ± 5.7, P < 0.0001; 29.8 ± 8.9 vs 14.2 ± 2.9, P < 0.0001). There were no significant differences between the values of SMA and SMV groups at 1 h (P = 0.28) and at 3 h (P = 0.71). In each group, plasminogen activity levels did not change significantly between the two measurements performed at 1 h and 3 h. CONCLUSION: We conclude that blood plasminogen activities decrease during early phases of both arterial and venous mesenteric ischemia which may be a useful marker for early diagnosis. METHODS: We performed laparotomy in 90 female Wistar-Albino rats (average weight 230 g). In sham groups (SL) (Groups I and II) the superior mesenteric artery (SMA) In SMA groups (Groups Ⅲ and Ⅳ) the SMA was ligated, and in SMV groups (Groups Ⅴ and Ⅵ) the SMV was ligated. On re-laparatomy 2 mL of blood was (SMV) were explored, but not tied. drawn at 1 h in groups I, III and V, and at 3 h in groups II, IV and VI. Plasminogen levels were made and groups were within groups and within each group. RESULTS: The mean plasminogen activity in the SL group was (25.1 ± 10.8 vs 13.7 ± 4.4, P <0.001) groups both at 1 h and at 3 h (29.8 ± 8.9 vs 15.1 ± 5.7, P <0.0001; 29.8 ± 8.9 vs 14.2 ± 2.9, P <0.0001). There were no significant differences between the values ​​of SMA and SMV groups at 1 In each group, plasminogen activity levels did not change significantly between the two measurements performed at 1 h and 3 h. CONCLUSION: We conclude that blood plasminogen activities decrease during early (P = 0.28) and at 3 h phases of both arterial and venous mesenteric ischemia which may be a useful marker for early diagnosis.