中文摘要：

目的探讨Nω硝基左旋精氨酸甲酯（Nω-nitro-左旋精氨酸methyl ester,L-NAME）对大鼠空间学习、记忆能力和海马CA1区毛细血管的影响。方法内导管成功埋植后,阻断剂组（L-NAME组）大鼠每日给予5μL的1μmol/μL L-NAME侧脑室注射,对照组（Sham组）每日给予5μL生理盐水侧脑室注射,持续4周。然后用Morris水迷宫测试大鼠空间学习和记忆能力,用试剂盒检测海马组织中NOS活性及NO含量,用体视学方法测定海马和海马CA1区总体积、海马CA1区毛细血管总长度、总表面积和总体积。结果水迷宫实验中L-NAME组的潜伏期显著长于Sham组（P=0.006）;L-NAME组海马组织中的NOS活性及NO含量均显著低于Sham组（P〈0.01）;L-NAME组海马体积、CA1区体积与Sham组比较差异无统计学意义（P〉0.05）;L-NAME组CA1区毛细血管总长度、毛细血管总表积、毛细血管总体积均较Sham组显著减少（P〈0.05）。结论 L-NAME可以导致大鼠空间学习、记忆能力下降和大鼠海马CA1区毛细血管总长度、总表面积以及总体积减少。

英文摘要：

Objective To determine the effect of Nω-nitro-L-arginine methyl ester（ L-NAME） on the spatial learning and memory abilities and the capillaries in CA1 region of rat hippocampus. Methods After the catheter was successfully inserted into lateral ventricle,in the L-NAME group,1 μmol / μL L-NAME was injected into the lateral ventricle of each rat at a dose of 5 μL once a day for 28 d,and in the sham group,the same dose of saline was injected into the lateral ventricle. Then,Morris water maze test was used to test the spatial learning and memory abilities. After the Morris water maze test,the NOS activity and NO content in the hippocampal tissues were measured. The total volume of hippocampus and hippocampus CA1 region,and the total length,total volume and total surface area of the capillaries in CA1 region were determined using stereological techniques. Results The water maze results showed that the time latency of the sham group was significantly shorter than that of the L-NAME group（ P = 0. 006）. Both NOS activity and NO content in the hippocampus of the L-NAME group were significantly lower than those of the sham group（ P 0. 01）. The total volume of the hippocampus and CA1 region had no significant difference between the L-NAME group and the sham group（ P 0. 05）. The total length,total surface area and total volume of the capillaries in the CA1 region of the L-NAME group were significantly less than those of the sham group（ P 0. 05）. Conclusion L-NAME induces significant decline in the spatial learning and memory abilities of the rats and significant decrease in the total length,total surface area and total volume of the capillaries in the CA1 region of rat hippocampus.