Blood–brain barrier damage in reperfusion following ischemia in the hippocampus of the Mongolian gerbil brain
Blood–brain barrier damage in reperfusion following ischemia in the hippocampus of the Mongolian gerbil brain
复制标题
蒙古沙鼠脑海马缺血再灌注时血脑屏障损伤
作者：
M. Shinnou;M. Ueno;H. Sakamoto;M. Ide
用光镜和电镜定性观察了静脉注射辣根过氧化物酶（HRP）对缺血蒙古沙土鼠脑海马血管通透性的影响。在右颈总动脉闭塞30分钟后再灌注90分钟，用固定剂灌注动物并处死。在灌注固定液前，将HRP注入股静脉。分别用四甲基联苯胺（TMB）和二氨基联苯胺（DAB）对HRP进行光学和电子显微镜检查。TMB对HRP的染色反应主要出现在手术侧海马的内侧或背侧，尤其是海马裂沿着的一些血管周围。沿海马裂沿着血管的超微结构检查显示，内皮细胞质中含有HRP填充的囊泡或空泡，紧邻基底层，似乎具有轻微的电子密度。在该区域还观察到肿胀的周细胞、肿胀的星形细胞足突和具有HRP填充的细胞质的血管周细胞。在这项研究中，它清楚地表明，血管内的大分子泄漏transendothelially，通过血管壁在海马裂，从血流中的内侧部分的海马在缺血后再灌注。这些发现表明，海马内侧部分海马裂沿着一些血管中的血脑屏障比其他脑区的血脑屏障更容易受到缺血性损伤。
Vascular permeability to intravenously injected horseradish peroxidase (HRP) was qualitatively examined in the hippocampus of ischemic Mongolian gerbil brains by light and electron microscopy. After 30 min of right common carotid artery occlusion followed by 90 min of reperfusion, the animal was perfused with a fixative and killed. Before the perfusion of the fixative, HRP was injected into the femoral vein. HRP was visualized with tetramethyl benzidine (TMB) and diamino‐benzidine (DAB) for light and electron microscopy, respectively. Staining reaction with TMB for HRP appeared in medial or dorsal portions of the operated side of the hippocampus, especially around some vessels along the hippocampal fissure. Ultrastructural examination in the vessels along hippocampal fissure revealed that the endothelial cytoplasm contained HRP‐filled vesicles or vacuoles in close proximity to the basal lamina, and seemed to be slightly electron‐dense. Swollen pericytes, swollen astrocytic foot processes and perivascular cells with HRP‐filled cytoplasm were also observed in that area. In this study, it was clearly demonstrated that intravascular macromolecules leaked transendothelially, through vessel walls in the hippocampal fissure, from the blood stream in the medial portions of the hippocampus during reperfusion following ischemia. These findings suggest that the blood–brain barrier in some vessels along the hippocampal fissure in the medial parts of the hippocampus is more vulnerable to ischemic insults than those in other brain areas.