fa تاثیر تزریق L- آرژنین بر یادگیری وابسته به وضعیت القا شده با WIN55, 212-2 در مدل یادگیری اجتنابی مهاری مقاله پژوهشی Original Research Article <p>Background and Objective: Cannabinoids are a class of psychoactive compounds that produce a wide array of effects in a large number of species. In the present study, the effects of bilateral intra-CA1 injections of L-arginine on WIN55, 212-2 induced state-dependent memory of passive avoidance task was examined in mice. Materials and Methods: One-trial step-down paradigm was used for the assessment of memory retention in adult male NMRI mice. Results: Post-training intra-CA1 administration of cannabinoid receptor agonist, WIN55, 212-2 (0.5 and 1 &micro;g/mouse), decreased the memory retrieval. The memory impairment induced by post-training administration of WIN55, 212-2 (1&micro;g/mouse) was restored by pre-test administration of the same dose of the drug, showing the state-dependent memory of WIN55, 212-2. Single intra-CA1 administration of L-arginine (0.3, 1 and 3 &micro;g/mouse) 5 min pre-test could not alter the memory retrieval. On the other hand, in the animals in which retrieval was impaired due to post-training administration of WIN55, 212-2 (1&micro;g/mouse), pre-test intra-CA1 administration of L-arginine (1 and 3 &micro;g/mouse), 24 hr after training restored memory retrieval. Furthermore, in the animals under influence of post-training administration of WIN55, 212-2 (1&micro;g/mouse), pre-test co-administration of non-effective doses of WIN55, 212-2 and L-arginine, increased the restoration of memory by the pre-test WIN55, 212-2. Conclusion: The findings of the present study suggest that NO system of dorsal hippocampus may play an important role in Win55,212-2-induced amnesia and WIN55,212-2 state-dependent memory.</p> Key words: WIN55, 212-2, State-dependent memory, Step-down passive avoidance task, L-arginine, NO, Mice 10 21 http://journal.zums.ac.ir/browse.php?a_code=A-10-4-516&slc_lang=fa&sid=1 Morteza Piri مرتضی پیری biopiri@yahoo.com 5200319475328460060338 5200319475328460060338 Yes Dept of Biology, Faculty of Basic Sciences, Islamic Azad University, Ardabil branch, Ardabil, Iran Mohammad Nasehi محمد ناصحی 5200319475328460060339 5200319475328460060339 No Dept of Biology, Faculty of Basic Sciences, Islamic Azad University, Garmsar branch, Semnan, Iran. Mohammadreza Zarrindast محمدرضا زرین دست 5200319475328460060340 5200319475328460060340 No Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.