深低温停循环下神经生长因子的脑保护作用研究

Experimental Study of Nerve Growth Factor and Neuroprotection during Deep Hypothermic Circulatory Arrest

目的建立一种新的深低温停循环模型,研究深低温停循环(DHCA)对兔大脑皮层、海马组织中神经细胞凋亡情况,探讨DHCA下神经生长因子的脑保护作用。方法健康新西兰大白兔幼兔(0.5 kg)20只,随机均分为2组:实验组(给予生长因子)和对照组(不给予生长因子)。在DHCA前、后不同时间窗监测血清S100β含量,并采用原位末端标记法(TUNEL染色法)观察和测定脑组织神经细胞凋亡的情况。对照分析两组不同时间窗S100β的变化以及神经细胞凋亡的情况。结果实验组幼兔在DHCA后神经细胞凋亡数目显著减少(P<0.05),在DHCA后30 min(T2)、1 h(T3)、3 h(T4)、5 h(T5)、12 h(T6)5个时间窗血清S100β蛋白含量明显低于对照组(P<0.05)。结论给予外源性神经生长因子能明显抑制海马以及皮层神经细胞的凋亡,对深低温停循环后的神经细胞有良好的保护作用。

OBJECTIVE To establish a model of deep hypothermie circulatory arrest （DHCA） and study the neural apoptosis in the hippocampus and cerebral cortex, investigate the protective effects of nerve growth factor（NGF） during DHCA. METHODS Twenty healthy baby rabbit （0.5kg）were randomly divided into two groups （ 10 rabbits per group） ： study group （preconditioning with NGF） and control group （without NGF）. S100β content of blood taken in different window around DHCA was measured. Neural apoptosis was identified by TUNEL in hippocampus CA1 region and cerebral cortex of brain. Comparely analysis the change of S100β and the expression of neural apoptosis in the hippocampus and cerebral cortex between two group. RESULTS The number of neural apoptotic cells in study group were decreased significantly during DHCA （ P 〈 0.05 ）. Serum S100β levels were significantly difference at post DHCA 30min （T2）, 1 h （T3） ,3 h（T4） ,Sh（TS）,12h（T6） between two group（ P 〈0.05）. CONCLUSION Exogenous NGF inhabit Neural apoptosis of hippocampus and cerebral cortex and has a protective effect on neuronal injury induced by DHCA.