大鼠上矢状窦闭塞后MMP-9在脑组织中的表达

目的探讨上矢状窦闭塞后基质金属蛋白酶-9(MMP-9)在脑组织中的表达与作用。方法采用结扎法建立大鼠上矢状窦闭塞模型,干湿重法测量脑组织含水量,免疫组化法检测MMP-9蛋白质的表达,同时观察是否有白细胞浸润。结果与对照组比较,上矢状窦闭塞后6h,脑组织含水量和MMP-9表达开始增加并伴极少量白细胞浸润,第1天后,脑组织含水量、MMP-9表达和白细胞浸润数量迅速上升,第5天到高峰,第7天开始下降,第14天虽明显减少,但仍然明显高于对照组;在整个脑水肿形成过程中,MMP-9的表达与脑组织含水量呈高度正相关(r=0.92,P<0.01),与浸润的白细胞记数也呈高度正相关(r=0.84,P<0.01)。结论上矢状窦闭塞后脑组织含水量显著增加,MMP-9的表达明显增强,内皮细胞和渗出的中性粒细胞中MMP-9的过度表达,在血-脑脊液屏障破坏、白细胞浸润及血管源性脑水肿形成过程中发挥了关键作用。

MMP-9 expression in brain after superior sagittal sinus obstruction in rats

Objective To investigate the significance of matrix metalloproteinase-9 (MMP-9) proteinexpression in the pathological process of brain edema formation after superior sagittal sinus obstruction in rats.Methods The superior sagittal sinus obstruction rat models were set up by ligation. Using dry-humid weightmethod, water content in brain tissue was measured. MMP-9 expression levels were detected byimmunohistochemistry method; leukocytes were counted at the same time. Results Compared with the controlgroup, the brain water content and the MMP-9 expression began to rise at 6 hours after superior sagittal sinusobstruction, accompanied by slight infiltration of leukocytes. They peaked at the 5th day and lasted till the 7th daybefore beginning to drop gradually. Although diminished obviously till 14 days after obstruction, they still remainedhigher than those in the control group. In the process of brain edema, MMP-9 expression positively related withbrain water content (r = 0.92, P < 0.01), as well as leukocyte infiltration (r = 0.84, P < 0.01). ConclusionMMP-9 expression levels elevate significantly after superior sagittal sinus obstruction. The over expression of MMP-9in endothelium and oozed neutrophilic leukocytes play a key role in brain blood barrier destruction, leukocyteinfiltration and vasogenic brain edema process.