The Effects Of Dengzhan Xixin On Matrix Metalloproteinase-9 And Metabolites After Cerebral Ischemia-reperfusion Injuries

Objectives The investigation studied the effects of Dengzhan Xixin on brain water content, blood-brain barrier(BBB) permeability, matrix metalloproteinase-9(MMP-9) expression, T2-weighted imaging(T2WI) and metabolites in the brain by in vivo nuclear magnetic resonance(NMR), the lesion ratio after cerebral ischemia-reperfusion injuries(IRI). Methods There were 165 rats in all, and the 130 rats were selected at random and individed into three groups, the sham-operated group, the ischemia-reperfusion group and the Dengzhan Xixin treatment group. The models of ischemia-reperfusion of middle cerebral artery in rats were established by placing an intraluminal suture, but the models of the sham-operated group (n=10) were placed 1.0 cm suture into internal carotid artery and sacrificed after l d for testing. The rats of the ischemia-reperfusion group (n=60) and the Dengzhan Xixin treatment group (n=60) were scored on neurologic function deficit after operation. The rats were sacrificed at reperfusion 6 h, 12 h, 1 d, 2 d, 4 d, 7 d after ischemia 1.5 h. The rats on the each time point of each group were checked for brain water content and BBB permeability (n=5), MMP-9 expression (n=5). The additional 35 rats were individed into three groups, the sham-operated group, the ischemia-reperfusion group and the Dengzhan Xixin treatment group. The rats were checked for the changes of T2WI and metabolites in the brain. The style of treatment was the same as before. The rats were sacrificed at reperfusion 1 d, 2 d, 4 d after ischemia 1.5 h. The rats of the sham-operated group (n=5) were killed for TTC staining after the test of NMR. The rats of the ischemia-reperfusion group (n=15) and the Dengzhan Xixin treatment group (n=15) were tested by NMR, then were sacrificed for checking the lesion ratio. Results In the ischemia-reperfusion group, brain water content and BBB permeability increased after reperfusion 6 h. The peak time of brain water content was at 4 d and BBB permeability was at 2 d. MMP-9 expressed at 6 h in ischemic hemisphere, and the peak time was at 2 d. In the treatment group brain water content, BBB permeability decreased and MMP-9positive cells were fewer than the ischemia-reperfusion group at the each time point. By TCC staining, the colour of the lesion area was pale, and in the treatment group the lesion ratio decreased. In the ischemia-reperfusion group and the Dengzhan Xixin treatment group, there were hyperintense signals in the injury region of T2WI. In the ischemia-reperfusion group after reperfusion 1 d, the ratio of NAA/Cr decreased and Cho/Cr increased. In the Dengzhan Xixin treatment group of the same time point as the ischemia-reperfusion group, the ratio of NAA/Cr increased and Cho/Cr decreased. Conclusions After cerebral IRI, brain water content, BBB permeability and MMP-9 expression increased. Dengzhan Xixin may decrease vasogenic brain edema, BBB permeability and influence the metabolites of brain, T2WI and the lesion ratio, which suggested Dengzhan Xixin may relieve cerebral IRI.