慢性脑缺血对青年和老年大鼠海马NOS阳性神经元的影响

本文利用组织化学方法观察了慢性脑缺血对青、老年大鼠海马ＮＯＳ阳性神经元的影响。慢性脑缺血采用双侧颈总动脉永久性结扎模型。结果：青年缺血１ 月组大鼠海马ＣＡ１、ＣＡ２～３ 和ＤＧ 亚区ＮＯＳ阳性神经元面数密度分别为２９．１±２．３、２３．５±２．１ 和３９．３±２．８，小于对照组相应三个亚区（４９．６±１．３、４９．３±２．１ 和６４．７±２．１），Ｐ＜ ０．０１；青年缺血３ 月组大鼠ＣＡ１、ＣＡ２～３ 和ＤＧ 亚区ＮＯＳ阳性神经元面数密度分别为４０．２±１．６、３９．３±２．５ 和４８．４±１．８，和对照组者相近，但大于缺血１ 月组（Ｐ＜ ０．０１）。老年缺血１ 月组大鼠海马各区ＮＯＳ阳性神经元面数密度分别为３９．６±１．５、３５．６±２．１ 和５４．７±２．５，小于老年对照组相应三个亚区（５５．８±１．７、５１．３±１．７ 和６４．９±１．９），Ｐ＜ ０．０１；老年缺血３ 月组大鼠各亚区ＮＯＳ阳性神经元面数密度分别为４３．１±２．４、３８．７±３．４ 和５４．７±３．２，仍然小于对照组，Ｐ＜ ０．０１。结果提示：慢性脑缺血可以影响大鼠海马ＮＯＳ阳性神经元，但青年和老年大鼠海马ＮＯＳ神经元对慢性脑缺血损伤的易感性和反应性不同。

EFFECTS OF CHRONIC CEREBRAL ISCHEMIA UPON HIPPOCAMPAL NOS POSITIVE NEURONS OF YOUNG AND AGED RATS

The present paper investigated the influence of chronic cerebral ischemia on hippocampal NOS positive neurons of young and aged rats. The chronic cerebral ischemia was induced by permanent bilateral carotid artery ligation (BCAL). The results showed: NOS positive neurons in CA1, CA2～3 and DG of hippocampus of the young rats after 1 month of BCAL were 29.1±2.3, 23.5±2.1 and 39.3±2.8 less than 49.6±1.3、49.3±2.1 and 64.7±2.1 of young control rats respectively, P<0.01; 3 months after BCAL, NOS positive neurons in CA1, CA2～3 and DG of the young rats were 40.2±1.6,39.3±2.5 and 48.4±1.8 respectively, more than that of the young rats after 1 month BCAL, P<0.01, approximately increased to that of control rats. NOS positive neurons in CA1, CA2～3 and DG of hippocampus of the aged rats after 1 month BCAL, were 39.6±1.5, 35.6±2.1 and 54.7±2.5, less than 55.8±1.7, 51.3±1.7 and 64.9±1.9 of the aged control rats respectively, P<0.01; however, 3 months after BCAL, NOS positive neurons in CA1, CA2～3 and DG of the aged rats were 43.1±2.4, 38.7±3.4 and 54.7±3.2 respectively, still less than that of aged control rats, P<0.01. Thus it was suggested chronic cerebral ischemia could affect the hippocampal NOS positive neurons of rats, and there was some difference between the young and the aged rats susceptibility and reacting pattern to chronic cerebral ischemia. (Figure 2 on plate 28)