学习记忆能力下降大鼠神经细胞增殖的研究

目的　观察学习记忆能力减退老年大鼠海马齿状回神经细胞的增殖。方法　Morris水迷宫筛选出学习记忆能力减退大鼠 (痴呆组 )与正常大鼠 (对照组 )。BrdU标记海马齿状回增殖细胞。TUNEL法标记DNA片段原位检测凋亡细胞。计数海马颗粒细胞层与海马门的BrdU阳性细胞与凋亡细胞数。结果　痴呆组与对照组大鼠相比 ,海马颗粒细胞层BrdU阳性细胞显著增加 (P <0 0 1) ,而凋亡细胞数无显著差异 (P >0 0 5 )。海马门BrdU阳性细胞数及凋亡细胞数均无显著差异 (P >0 0 5 )。结论　学习记忆能力减退的老年大鼠海马齿状回神经细胞增殖能力减低。

A study on neuronal proliferation in the learning and memory ability impaired aged rats

Objective To study neuronal proliferation in dentate gyrus of aged rats.Methods According to the mean time of escape latencies,experimental aged rats were divided into normal control group and dementia group by Morris water maze. BrdU was used to label the proliferation of cells in dentate gyrus,and TUNEL was used to identify apoptotic cells in the same area. Then BrdU positive cells and TUNEL positive cells in granule cell layer and hilus were counted compared respectively.Results In granule cell layer,BrdU positive cells of the dementia group were more than those of the control group( P< 0.01),but TUNEL positive cell count showed no difference between the two groups( P> 0.05).Moreover,there was no difference both of BrdU positive cells and TUNEL positive cells in hilus( P> 0.05).Conclusion The reduction of neoronal proliferation in dentate gyrus may be responsible for the damage of learning and memory ability in aged rats.