捕食应激过程中大鼠脑边缘系统一氧化氮合酶神经元的变化  

Changes of the numbers and activity of NOS positive neurons in the rat limbic system during predator stress

作　　者：郭建[1] 陈泳宏[2] 刘平[2] 盛春宁[2] 骆云[2] 张留宝[2] 

机构地区：[1]南京师范大学生命科学学院 [2]第二军医大学南京军医学院组织学与胚胎学教研室,南京210099

出　　处：《动物学报》2004年第5期759-764,共6页ACTA ZOOLOGICA SINICA

基　　金：南京林业大学留学归国人员基金资助项目 (No .G2 0 0 2 2 3 )资助~~

摘　　要：探讨应激状态下大鼠脑边缘系统内一氧化氮合酶 (Nitricoxidesynthase,NOS )阳性神经元的变化及这种变化与脑神经元损伤发生的关系。采用捕食应激动物模型 ,将 80只雄性SD大鼠随机分为 3组 :对照组 (n =2 0 )、单纯捕食应激组 (n =30 )、加强捕食应激组 (n =30 )。采用还原型尼克酰胺腺嘌呤二核苷酸黄递酶(NADPH d)组织化学方法 ,研究应激后 1、 3、 6、 12、 2 1、 30dNOS阳性神经元的分布规律。结果表明 :对照组NOS活性平稳 ,但应激后NOS活性变化明显。与对照组比较 ,应激 1- 3d ,单纯应激组和加强应激组NOS阳性神经元数目在皮质、纹状体、海马、下丘脑等部位增多 ,即NOS活性升高 ;第 4 - 12d ,NOS活性进一步升高 ,除皮质外与对照组相比具显著性差异 (P <0 0 1) ;其中 ,应激单纯组和加强组海马和下丘脑室旁核分别在第 6d、第 12dNOS活性最高。从第 13d起NOS阳性神经元的活性开始逐渐降低 ;到第 30dNOS活性下降明显 ,但其活性仍高于对照组 (P <0 0 5 )。对于同一时间点而言 ,与对照组相比 ,加强应激组的NOS活性变化大于相应的单纯应激组。结果提示 :NOS活性程度与心理应激程度密切相关 ;This study investigates changes of nitric oxide synthase (NOS) positive neurons in the rat limbic system under the predator stress, particularly in brain areas such as the cerebral cortex, hippocampus, striatum, paraventricular hypothalamic nucleus and periventricular hypothalamic nucleus; and explores the role of nitric oxide (NO) on the injury to neuron in the rat limbic system. Eighty male Sprague-Dawley rats were randomly divided into three groups: Group C for control (n=20), Group S for simple predator stress (n=30) and Group S-I for intensive predator stress (n=30). Group S rats were exposed to non-injurious exposure to a cat and background noise for 10 minutes a day. Group S-I rats were treated with the same protocol as Group S, but 4 hours later, the rats were exposed to background noise without a cat for 10 minutes. The change of NOS positive neurons in the limbic system of the rats was inspected with the histochemical method of NADPH-diaphorase after predator stress 1 d, 3 d, 6 d, 12 d, 21 d and 30 d. NOS activity was stable in Group C, but the change was significantly in Group S and Group S-I. The number of NOS positive neurons increased in the limbic system during early stage of stress (1-3 d), the activity of NOS was increased too. During stress 4-12 day, the activity of NOS increased significantly (P<0.01). From the 13th day, the activity of NOS in the limbic system began to decrease gradually, on the 30th day the decrease was obvious, however, the NOS activity of Group S and Group S-I was still higher than group C (P<0.05). The results indicate the increases of NOS activity are positively correlated to the severity of psychological stress. Also, nerve toxicity induced by exceeding NO during stress may be one of the causes of damage to neurons in the limbic system of the stressed rats.

关 键 词：NOS活性 对照组 捕食应激 边缘系统 NOS阳性神经元 大鼠 一氧化氮合酶 动物学 雄性 皮质 

分 类 号：Q42[生物学—神经生物学]