杨丽君+崔红

[摘要] 目的 探讨大鼠缺血低氧脑损伤对于神经元和髓鞘的影响情况。 方法 将3日龄SD新生大鼠随机分为对照组和缺血低氧处理组，对照组不予任何特殊处理，缺血低氧处理组大鼠行左颈总动脉结扎术后休息1～2 h入封闭容器，充以8%O2+92%N2的混合气体，处理时间为120 min，之后恢复正常氧供。待造模完成后3 d时进行尼氏小体染色探讨两组大鼠神经元的情况，造模后7 d进行劳克坚牢蓝染色探讨两组大鼠的髓鞘情况。 结果 尼氏染色结果提示，与对照组相比，缺血低氧处理之后大鼠脑组织中的神经元尼氏小体染色密度明显降低；劳克坚牢蓝染色结果显示，与对照组相比，缺血低氧处理组的髓鞘明显受损。 结论 大鼠缺血低氧性脑损伤对脑组织的神经元和髓鞘造成了一定程度的影响，进而导致脑组织相关的功能损伤。

[关键词] 脑损伤；缺血；低氧；神经元；髓鞘

[中图分类号] R741 [文献标识码] A [文章编号] 1673-9701（2017）25-0030-03

Effects of hypoxic-ischemic brain damage on neurons and myelin in immature neonatal rats

YANG Lijun CUI Hong

Department of Pediatrics， Beijing Friendship Hospital， Capital Medical University， Beijing 100050， China

[Abstract] Objective To investigate the effects of ischemia and hypoxic brain injury on neurons and myelin in rats. Methods Three-day-old SD neonatal rats were randomly divided into two groups including control group and ischemia-hypoxia treatment group. The control group wasnt given any special treatment. Rats in the ischemia and hypoxia treatment group were put into the closed container after left common carotid artery ligation operation and resting 1-2 hours， and the container was filled with 8%O2+92%N2 mixed gas， with the treatment time of 120 minutes， afterwards returning to normal oxygen supply. The neurons in the two groups were examined by Nedinite staining at 3 days after the completion of the modeling. The myelin sheathes of the two groups were explored by Luxol Fast Blue staining at 7 days after the compeletion of the modeling. Results The results of Nissl staining showed that， compared with that of the control group， the density of neonatal body staining was significantly decreased in the brain tissue of rats after ischemia and hypoxia treatment. Luxol Fast Blue staining results showed that the myelin sheath of the ischemic hypoxia treatment group was significantly impaired， compared with that of the control group. Conclusion Hypoxic-ischemic brain damage in rats has a certain effect on the neurons and myelin sheath of brain tissue， leading to brain tissue-related functional damage.

[Key words] Brain injury； Ischemia； Hypoxia； Neurons； Myelin sheath

缺氧缺血性腦损伤（hypoxia ischemia brain damage，HIBD）是围产期引起早产儿和正常足月儿大脑损伤和长期神经系统后遗症的最重要因素[1]，研究发现HIBD是导致新生儿死亡的重要原因，也是引起脑瘫等严重后遗症的重要原因[2]。有证据表明，在发达国家HIBD的发生率为1‰～8‰，不发达国家发病率甚至高达26‰[3，4]。造成HIBD的原因很多，如出生时产程延长、胎儿脐带绕颈等均有罹患HIBD的更高风险[5]，此外，早产是造成新生儿HIBD的另外一个重要的危险因素[6，7]。由于早产儿结构的不成熟，对于缺氧缺血的损伤反应更为剧烈，主要表现为脑室周围白质软化（periventricular leukomalacia，PVL）[8-10]。……