中文摘要：

目的研究出生前后不同浓度慢性铝暴露后年轻大鼠海马NO含量和nNOS表达的变化,探讨铝损害学习记忆的突触机制。方法对照组、低剂量和高剂量组大鼠从孕期开始分别自由饮用蒸馏水15mmol·L^-1和30mmol·L^-1的A1C13水溶液;采用原子吸收石墨炉法测定血铝和脑铝含量;跳台法测试学习记忆能力;硝酸还原酶法检测NO含量;免疫组化方法观察nNOS阳性细胞表达。结果与对照组相比,两铝暴露组大鼠血铝和脑铝含量明显升高,学习记忆能力明显下降,海马NO含量明显降低且nNOS阳性神经元表达明显减少。结论出生前后慢性铝暴露损害了大鼠的学习记忆行为,可能与海马NO含量减少及nNOS神经元表达降低有关。

英文摘要：

Aim To study the change of NO and nNOS in hippocampus of young rats after chronic aluminum exposure of different concentration from prenatal to postnatal period,to go deep into the synaptic mechanism of that aluminum impairs learning and memory capacity.Methods Rats of control,low-dose and high-dose groups were treated from gestation with distilled water and AlCl3 water solution with concentration of 15 mmol·L^-1 and 30 mmol·L^-1 Al^3＋ respectively.The aluminum concentrations of brain and blood were measured by Atomic absorption spectrometry（AAS）.The step-down test was used to monitor the learning and memory ability.The content of NO was tested by nitrate reductase method.The expression of nNOS positive cells were observed with immunohistochemistry.Results Compared with the control group,in the Al3＋ exposed groups,the blood and brain aluminum were significantly higher,the ability of learning and memory remarkably decreased,the hippocampal intracellular NO content was obviously reduced,the nNOS positive cells in the CA1 and CA3 region of hippocampus significantly decreased.Conclusions Aluminum exposure from prenatal to postnatal impaired the learning and memory ability of young rats,and the impairment might be related to the decrease of intracellular NO content and the expression of nNOS positive cells in hippocampus.