nNOS选择性拮抗剂7-硝基吲唑促进成年小鼠脑缺血后神经元再生

nNOS specific inhibitor 7-nitrioindazole up-regulates the neurogenesis after focal cerebral ischemia in the adult mice

目的研究nNOS选择性拮抗剂7-硝基吲唑对脑缺血后神经元再生的影响。方法大脑中动脉阻塞法制备局灶性脑缺血/再灌注模型。腹腔注射7-硝基吲唑(30 mg.kg-1)。B rdU、NeuN标记法测定海马齿状回的细胞扩增及新生细胞的分化,跳台实验法测定动物的学习记忆能力。结果在脑缺血后d 8缺血侧海马齿状回的B rdU阳性细胞数比对照侧多大约3倍,7-硝基吲唑进一步促进了脑缺血所诱发的海马齿状回神经细胞扩增,并促进新生细胞的存活,改善脑缺血小鼠的学习记忆功能。结论nNOS对脑缺血诱发的海马齿状回神经元再生有重要作用。

Aim To explore the effect of nNOS specific inhibitor 7-nitrioindazole（ 7-NI ） on the neurogenesis after focal cerebral isehemia in the adult mice dentate gyrus. Methods Focal cerebral isehemia was induced by middle cerebral artery occlusion （MCAO）. A bromodeoxyuridine （ BrdU ） method was used to identify the proliferated cells in hippoeampal dentate gyrus. Step-down test was performed to assay the learning and memory function. Results The number of BrdU ^＋ cells was increased in the ipsilateral but not eontralateral dentate gyrus after focal cerebral ischemia. 7-NI promoted the increment in the ipsilateral dentate gyrus significantly. 7-NI also improved the survival of the newborn cells, as well as the learning and memory function of ischemic mice. Conclusion Our results indicate that nNOS down-regulates the neurogenesis after focal cerebral ischemia.