Objective       To determine the effect of adenovirus mediated over-expression of Fibulin-5 on blood brain barrier leakage in rats after cerebral ischemia/reperfusion (I/R) injury and investigate the possible underlying potential mechanism.       Methods       A total of 112 adult male Sprague-Dawley rats were randomly divided into sham operation group

cerebral I/R group

I/R plus AD-F

ibulin-5 group

and I/R plus AD-HK group. Adenovirus carrying fibulin-5 gene (AD-Fibulin-5) or blank adenovirus (AD-HK) were injected into the right cortex and hippocampus of the rats from the latter 2 groups. In 7 d after gene transfer

the rats

except for those of the sham operation group

underwent 90 min of ischemia and then were reperfused for 24 h. The expression of fibulin-5 and occluding in the brain tissue were detected by Western blotting

RT-PCR and immunohistochemical assay. Evan-blue extravasation was used to measure the permeability of blood brain barrier. TTC staining was employed to observe the cerebral infarct volume. Neurological function was also evaluated.       Results       Intervention of AD-Fibulin-5 resulted in significantly increased expression of fibulin-5 at protein and mRNA levels (

P

0.01)

smaller amount of Even-blue leakage (

P

0.01)

enhanced expression of occludin (

P

0.01)

  obviously decreased infarct volumes (

P

0.01)

obviously milder neurological impairment (

P

0.01) when compared to the other groups.       Conclusion       Over-expression of Fibulin-5 attenuates blood brain barrier leakage in rats after cerebral I/R injury

which might be due to its enhancing the expression of occludin.