Hatashita S, Hoff J T
Section of Neurosurgery, University of Michigan, Ann Arbor 48109.
Adv Neurol. 1990;52:327-33.
We studied how changes in BBB function are related to the development of ischemic brain edema. Focal cerebral ischemia was produced by left MCA occlusion in rats. The permeability of the BB to small or large molecules was evaluated qualitatively by the extravasation of EB or NaFl dyes and quantitatively by the uptake index of 125I-BSA or 14C-sucrose. Brain water content was determined by specific gravity. Measurements were made from the cortical core of the MCA territory within 14 days of occlusion. Water content progressively increased within 2 days of occlusion and then gradually decreased up to 14 days. Lightly stained EB areas were located only in the proximal portion of the ischemic core. The incidence of NaFl extravasation was similar to that of EB within 2 days of occlusion but was greater than that of EB 3 days after occlusion. NaFl staining diffusely extended into the ischemic core. Although the index of 125I-BSA increased only slightly within 2 days of occlusion, a marked increase in 125I-BSA was found after 3 days. The index of 14C-sucrose increased gradually after occlusion, reaching a peak at 8 days. These findings indicate that the change in BBB permeability is minimal in ischemic brain tissue when the accumulation of edema fluid is maximal and suggest that BBB alteration in ischemic brain tissue may be associated with the stabilization or resolution of the ischemic lesion.
我们研究了血脑屏障（BBB）功能变化与缺血性脑水肿发展之间的关系。通过大鼠左侧大脑中动脉（MCA）闭塞制造局灶性脑缺血。通过伊文思蓝（EB）或氟化钠（NaFl）染料外渗定性评估BBB对小分子或大分子的通透性，并通过125I-牛血清白蛋白（BSA）或14C-蔗糖摄取指数进行定量评估。通过比重法测定脑含水量。在闭塞后14天内从MCA区域的皮质核心进行测量。含水量在闭塞后2天内逐渐增加，然后直至14天逐渐下降。轻度染色的EB区域仅位于缺血核心的近端部分。NaFl外渗的发生率在闭塞后2天内与EB相似，但在闭塞后3天大于EB。NaFl染色广泛延伸至缺血核心。虽然125I-BSA指数在闭塞后2天内仅略有增加，但在3天后发现125I-BSA显著增加。14C-蔗糖指数在闭塞后逐渐增加，在8天达到峰值。这些发现表明，当水肿液积聚最大时，缺血脑组织中BBB通透性变化最小，并提示缺血脑组织中的BBB改变可能与缺血性病变的稳定或消退有关。
