Abstract: Objective To study the effects of morroniside on the expression of matrix metalloproteinase (MMP) -2 and MMP-9 in the peri- infarct cortex 3 days after cerebral ischemia- reperfusion. Methods 15 male Sprague-Dawley rats were randomly divided into sham group (n=3), ischemia group (n=3), and morroniside groups (low, medium and high dosage groups, n=3). The middle cerebral artery were occluded for 30 min, and re-perfused. Morroniside was administered intragastrically once a day at dose of 30 mg/kg, 90 mg/kg and 270 mg/kg 3 hours after operation. The expression of MMP-2 and MMP-9 in peri-infarct cortex were detected with immunohistochemistry staining 3 days after operation. Results The expression of MMP-2 and MMP-9 increased in the ischemia group compared with the sham group (P<0.01), and it decreased in all the morroniside groups compared with the ischemia group (P<0.01). Conclusion Morroniside could decrease the expression of MMP-2 and MMP-9 in the peri-infarct cortex 3 days after ischemia, suggesting protecting the function of blood-brain barrier from ischemia.

Key words: cerebral ischemia-reperfusion, morroniside, matrix metalloproteinase-2, matrix metalloproteinase-9, rats