Behavioral alterations following a hypoxic-ischemic brain injury in neonatal rats and the effects of treatment with caspase inhibitor.

半胱氨酸天冬氨酸氨基转移酶被认为在大鼠脑缺氧缺血后迟发性神经细胞死亡中起关键作用。用Moris水迷宫试验评估新生儿缺血性损伤后运动和认知功能障碍的特征。此外，我们还观察了Caspase抑制剂对缺氧缺血性脑损伤后认知功能改变的影响。1)缺氧缺血性脑损伤后的行为改变1)采用单侧颈总动脉结扎加8%氧气暴露2小时的方法建立7日龄大鼠缺氧缺血性脑损伤模型。这些动物在28日龄时接受了水迷宫测试。缺血大鼠游泳速度与对照组比较差异无统计学意义。HI大鼠到达固定平台的平均潜伏期较对照组显著延长，缺血组大鼠不能无错误地完成测试。2)组织学改变与学习能力的关系不同缺血动物的脑损伤程度不同。计数同侧海马CA1区神经细胞数。3)半胱氨酸天冬氨酸氨基转移酶抑制剂对行为改变的影响。BAF对大鼠学习能力无明显影响。

Caspases are believed to play a key role in the delayed neuronal cell death observed in the rat brain following hypoxic-ischemic (HI) insult. The characterization of motor and cognitive dysfunctions following neonatal ischemic injury was assessed by using Moris water maze test. Furthermore we investigated the effect of caspase inhibitor administration on the cognitive alterations following HI insult.1) Behavioral alterations following a hypoxic-ischemic brain injuryHI model animals were obtained by the combination of monolateral carotid ligation and exposure to 8 % oxygen for 2 hours in 7-day-old rats. The animals were tested in a water maze test at 28 days old. No significant differences were found between ischemic and control rats in the speed of swimming. The average latency for HI rats to reach the fixed platform was significantly prolonged in comparison with control rats, and the ischemic group rats were unable to perform the test without mistakes.2) The relation between the histological findings and learning abilityThe extend of the brain damage was not the same in all ischemic animals. The number of neuronal cells in the ipsilateral hippocampal CA1 region was counted. There was no significant relation between the histological findings and the extend of behavioral alternations statistically.3) The effects of caspase inhibitor (BAF) on the behavioral alternationsBAF was injected intraperitoneally after HI loading. No significant effect in learning ability was observed in BAF treated rats.