摘要
目的观察在离心机高Ｇ值反复作用下，血脑屏障通透性的变化特点，为高Ｇ值作用下脑功能改变的解释提供生理学依据。方法选雄性大鼠２０只，分为对照组及＋ＧＺ暴露后不同时间组，实验组经增长率为１Ｇ／ｓ，持续３ｍｉｎ的＋１０ＧＺ暴露３次，立即经大鼠心脏灌注镧固定液，开颅取脑，制成切片，置透射电镜下观察。结果＋ＧＺ重复暴露３次后即刻，即见镧颗粒通过少数开放的毛细血管内皮细胞间的紧密连接，沉积于血管外围；暴露后１ｈ及６ｈ，可见大部分毛细血管内皮细胞间的紧密连接开放，镧颗粒弥漫性地分布于神经细胞间隙，部分镧颗粒已进入神经细胞内部，分布于线粒体、内质网等细胞器的表面；暴露后２４ｈ，则见镧颗粒仅局限分布在血管腔内，毛细血管外的间隙则未见镧颗粒沉积，与对照组大鼠相似。结论＋１０ＧＺ／３ｍｉｎ重复作用３次可引起大鼠血脑屏障通透性增加，这种改变是可逆的。其可能在＋ＧＺ致脑水肿的发生、发展过程中起重要作用。
S Objective To explore the changes of blood brain barrier(BBB) permeability after repeated +G Z exposures in rats,using lanthanum trace labeling with electron microscopy. Methods Twenty rats were devided into 5 groups, and 1 G Z group served as control. The other 4 groups underwent repeated +10 G Z/3 min exposures(3 times,with 30 min interval in between). Results The results showed that,immediately after repeated +G Z exposures, a few tight junctions of endothelial cell opened through which the lanthanum entering the outside of capillaries. Most tight junctions of endothelial cell opened through which the lanthanum entering the extra cellular space and the mitochondria and endoplasmic reticulum of neurons 1 h and 6 h after repeated +G Z exposures. The lanthanum was only seen in the lumens of capillaries but not in the extravessels 24 h after repeated +G Z exposures. Conclusion It is suggested that the increased BBB permeability after three +10 G Z/3 min exposures is reversible,which may play an important role in the development of brain edema.
出处
《中华航空航天医学杂志》
CSCD
1997年第1期31-34,共4页
Chinese Journal of Aerospace Medicine
关键词
加速度
脑损伤
血脑屏障
硝酸镧
Acceleration Brain injury Blood brain barrier Lanthanum nitrate
