Ohno M, Yamamoto T, Watanabe S
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
Brain Res. 1993 Dec 31;632(1-2):36-40. doi: 10.1016/0006-8993(93)91135-f.
In order to elucidate the roles of hippocampal nitric oxide (NO) synthesis in working and reference memory performance of rats, the effects of intrahippocampal injections of the NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME), on this behavior were examined with a three-panel runway task. In the working memory task, L-NAME, injected bilaterally at 10 and 32 micrograms/side into the dorsal hippocampus, significantly increased the number of errors (attempts to pass through two incorrect panels of the three panel-gates at four choice points). This effect of intrahippocampal L-NAME (32 micrograms/side) on working memory was attenuated by concurrent injection of 100 micrograms/side L-arginine, the precursor of NO. Intrahippocampal injection of the inactive isomer D-NAME at doses up to 32 micrograms/side had no effect on the number of working memory errors. In the reference memory task, neither L-NAME nor D-NAME affected the number of errors when injected into the hippocampus at doses up to 32 micrograms/side. These results suggest that processes mediated by NO synthesis in the hippocampus are involved in working memory, but not in reference memory.
为了阐明海马体一氧化氮（NO）合成在大鼠工作记忆和参考记忆表现中的作用，我们使用三板式跑道任务研究了海马体内注射NO合酶抑制剂NG-硝基-L-精氨酸甲酯（L-NAME）对这种行为的影响。在工作记忆任务中，双侧以10微克/侧和32微克/侧的剂量向背侧海马体注射L-NAME，显著增加了错误次数（在四个选择点试图穿过三板门中两个错误板的尝试次数）。海马体内注射L-NAME（32微克/侧）对工作记忆的这种影响可通过同时注射100微克/侧的NO前体L-精氨酸而减弱。海马体内注射剂量高达32微克/侧的无活性异构体D-NAME对工作记忆错误次数没有影响。在参考记忆任务中，当以高达32微克/侧的剂量注射到海马体中时，L-NAME和D-NAME均未影响错误次数。这些结果表明，海马体中由NO合成介导的过程参与工作记忆，但不参与参考记忆。
