Cav-1,MMP-2/9, Tight Junction Protein Expression And Early Blood-brain Barrier Damage During Cerebral Ischemia In Rats

Objective:To investigate the relationship between cav-1, MMP-2/9, tight junction proteins (claudin-5, occludin) expression and early blood-brain barrier damage during cerebral ischemia in rats.Methods:72healthy SD rats were randomly divided into control group, sham operation group,1.5h,3h and4.5h ischemia group, ischemia group were prepared by middle cerebral artery occlusion model, sham operation group were received the same surgery without middle cerebral artery occlusion. Each group was further divided into two subgroups, respectively used for Evans blue staining and immunohistochemistry experiments. The rats were sacrificed at different time end, TTC staining and neurobehavioral ratings evaluate the success model; Evans blue content detection evaluate the change of BBB permeability; Immunohistochemistry detect the expression of cav-1, MMP-2/9, claudin-5and occludin.Results:After cerebral ischemia, neurological deficit symptoms were appeared in rats, TTC staining confirmed success of MCAO model; In the early phase of cerebral ischemia (before4.5h),Evans blue was significantly increased in ischemic side, Immunohistochemistry showed that cav-1and MMP-9up-regulated, claudin-5down-regulated, whereas without MMP-2and occludin expression significant change.Conclusions:In early cerebral ischemia, the expression of MMP-9and claudin-5degradation participate the early blood-brain barrier damage, rapid MMP-9activation or secretion may be mediated by cav-1, MMP-2and occludin have no obvious correlation with early BBB damage.