Protective Effect of Angiopoietin-1 on the Blood Brain Barrier after Focal Cerebral Ischemia-Reperfusion Injury in Rats

Objective: To observe the protective effect of angiopoietin-1 (Ang-1) on the blood brain barrier (BBB) after focal cerebral ischemia-reperfusion injury (CIRI) in rats. Methods: Forty male healthy Wister rats were selected. The focal CIRI models were established using middle cerebral artery occlusion and 30 rats were divided into sham-operation group (n = 10), normal saline group (NS) group (n = 10) and Ang-1 treatment group (n = 10). The rats were killed 48 h after reperfusion, and brain water content, BBB permeability, cerebral infarction volume and neurological severity scores in rats were detected respectively. Results: 48 h after reperfusion, both the brain water content and Evans blue (EB) content in Ang-1 treatment group were significantly lower than in NS control [(68.69 +/- 4.46) % vs. (79.08 +/- 4.12) %, P < 0.001; (98.60 +/- 10.56) mu g/g vs. (379.90 +/- 21.64) mu g/g, P < 0.001], and there was no statistical significance by comparison to those in sham-operation group [(65.37 +/- 3.28) %; (89.62 +/- 8.65) mu g/g, P > 0.05)]. The cerebral infarction volume in Ang-1 treatment group was markedly smaller than in NS group [(0.119 +/- 0.022) cm(3) vs. (0.407 +/- 0.036) cm(3), P < 0.001], and no significant difference was presented when compared with sham-operation group [(0.104 +/- 0.011) cm(3), P > 0.05]. Besides, the neurological severity scores in Ang-1 treatment group were notably lower than in NS group [(1.83 +/- 0.29) points vs. (2.87 +/- 0.34) points, P < 0.001], but higher than in sham-operation group [(0.79 +/- 0.11) points, P < 0.001]. Conclusion: Ang-1 can decrease BBB permeability after focal CIRI in rats, so it has a protective effect on CIRI.