宫内缺氧对新生小鼠额叶皮质神经元内nNOS表达及对成年小鼠学习记忆能力的影响

为探讨孕鼠宫内缺氧对新生小鼠发育时期额叶皮质神经元内nNOS表达及对成年小鼠学习记忆能力的影响,本研究采用Tapanainen建立的缺氧模型致胎龄13、15、17d小鼠宫内缺氧,然后采用Nissl染色观察新生鼠发育时期P1、P7、P14、P28、P90额叶皮质内神经元的数量和形态变化;免疫组织化学染色方法观察新生鼠发育时期P1、P7、P14、P28、P90脑组织内nNOS阳性神经元的表达;Morris水迷宫实验检测P90小鼠的学习和记忆能力。结果显示:与正常组比较,宫内缺氧组小鼠额叶皮质神经元数量明显减少,额叶皮质神经元内nNOS的表达明显减弱。宫内缺氧组小鼠逃避潜伏期延长及穿环次数明显减少。以上结果提示宫内缺氧可导致新生鼠额叶皮质神经元数量明显减少及nNOS的表达也明显减弱,并引起成年小鼠学习记忆能力降低。

Effects of hypoxia in uterus on the frontal cortex neurons expressing nNOS in mice during postnatal development and the ability of learning and memory in adult mice

In order to elucidate the effects of hypoxia in uterus on the frontal cortex neurons expressing nNOS in mice during postnatal development and the ability of learning and memory in adult mice,the model of hypoxia in uterus established by Tapanainen and the mice during E13,E15,E17 cause hypoxia in uterus was used.The number and morphologic change of the frontal cortex neurons during postnatal development(P1,P7,P14,P28,P90)with hypoxia within the uterus were observed by Nissl staining,the expression of nNOS in the frontal cortex neurons of mice during postnatal development(P1,P7,P14,P28,P90)with hypoxia within the uterus was examined with immunohistochemical method,and the ability of learning and memory in adult mice was checked by Morris water maze.The results showed that compared with control group,the number of neurons in frontal cortex of mice during postnatal development in hypoxic group reduced significantly,the expression of nNOS in frontal cortex neurons of mice during postnatal development in hypoxic group decreased obviously.Latency to escape platform became longer and the wearing numbers reduced significantly.The present results indicate that intrauterine hypoxia reduces the number of neurons and the expression of nNOS in frontal cortex of mice during postnatal development,and the ability of learning and memory in adult mice.