血-脑屏障和血-神经屏障内皮细胞的比较研究

目的研究血-脑屏障与血-神经屏障内皮细胞在超微结构、通透性及标记物表达方面的差异。方法取大鼠前额叶皮层和坐骨神经。用电镜观察内皮细胞的超微结构；用免疫组织化学的方法检测转铁蛋白受体（OX-26）和内皮屏障抗原（EBA）的表达及微血管周围纤维蛋白原外渗。结果电镜显示，血脑屏障和血-神经屏障微血管均为紧密连接，但血-神经屏障吞饮小泡较血-脑屏障多（P〈0．05）。免疫组织化学显示，血-神经屏障OX-26和EBA阴性表达，微血管周围可见微量纤维蛋白原外渗；血-脑屏障OX-26和EBA均强阳性表达，微血管周围未见纤维蛋白原外渗。结论血-脑屏障与血-神经屏障内皮细胞虽然均为紧密连接，但两者在吞饮小泡数量、标记物表达及通透性等方面均存在差异。

Difference of Endothelial Cell in Ultrastructure, Markers and Permeability between Blood-Brain Barrier and Blood-Nerve Barrier

Objective To investigate the difference of endothelial cell (EC) in ultrastructure,markers and permeability between blood-brain barrier (BBB) and blood-nerve barrier (BNB).MethodsThe rat brain cortex and sciatic nerve were removed.Ultrastructure of endothelial cell was observed with electron microscopy.Employing immunohistochemical (IHC)staining,the relative distribution was determined for the OX-26,endothelial barrier antigen (EBA)and extravasated fibrinogen around microvessels.ResultsMicrovessels both in BBB and in BNB did share the same tight junctions.However,BNB had a significantly larger number of vesicles than that of BBB.Microvessels in BNB did not express the OX-26 and EBA,but staining weakly positive for fibrinogen,while microvessels in BBB showed strong positive for OX-26 and EBA,perivascular staining of fibrinogen had not been seen.ConclusionTight junctions were present in both BBB and BNB endothelial cell,but there was a significant difference between them in the number of the pinocytotic vesicles,markers expression and permeability.