title: Activation of endocannabinoid system in the rat basolateral amygdala improved scopolamine-induced memory consolidation impairment.
abstract: The current study was designed to examine the involvement of cannabinoid CB1 receptors in the basolateral amygdala (BLA) in scopolamine-induced memory impairment in adult male Wistar rats. The animals were bilaterally implanted with the cannulas in the BLA and submitted to a step-through type passive avoidance task to measure the memory formation. The results showed that intraperitoneal (i.p.) administration of different doses of scopolamine (0.5-1.5mg/kg) immediately after the training phase (post-training) impaired memory consolidation. Bilateral microinjection of the cannabinoid CB1 receptor agonist, arachydonilcyclopropylamide (ACPA; 1-4ng/rat), into the BLA significantly improved scopolamine-induced memory consolidation impairment. On the other hand, co-administration of AM251, a cannabinoid CB1 receptor antagonist (0.25-1ng/rat, intra-BLA), with an ineffective dose of scopolamine (0.5mg/kg, i.p.), significantly impaired memory consolidation and mimicked the response of a higher dose of scopolamine. It is important to note that post-training intra-BLA microinjections of the same doses of ACPA or AM251 alone had no effect on memory consolidation. Moreover, the blockade of the BLA CB1 receptors by 0.3ng/rat of AM251 prevented ACPA-induced improvement of the scopolamine response. In view of the known actions of the drugs used, the present data pointed to the involvement of the BLA CB1 receptors in scopolamine-induced memory consolidation impairment. Furthermore, it seems that a functional interaction between the BLA endocannabinoid and cholinergic muscarinic systems may be critical for memory formation.
authors.affiliation: Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Seyed Ershad
authors.initials: SE
authors.lastname: Nedaei
authors.affiliation: Department of Animal Biology, School of Biology and Center of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, Tehran, Iran.
authors.forename: Ameneh
authors.initials: A
authors.lastname: Rezayof
authors.affiliation: Department of Physiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Pourmotabbed
authors.affiliation: Cognitive and Neuroscience Research Center (CNRC), Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Nasehi
authors.affiliation: Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran; Department of Pharmacology, School of Medicine and Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran; School of Cognitive Sciences, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran. Electronic address: zarinmr@ams.ac.ir.
authors.forename: Mohammad-Reza
authors.initials: MR
authors.lastname: Zarrindast
mesh_terms: D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology; D066272:Basolateral Nuclear Complex / Q000187:drug effects* / Q000378:metabolism*; D063386:Cannabinoid Receptor Agonists / Q000494:pharmacology; D063387:Cannabinoid Receptor Antagonists / Q000494:pharmacology; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D063388:Endocannabinoids / Q000378:metabolism*; D008297:Male; D000069077:Memory Consolidation / Q000187:drug effects / Q000502:physiology; D008569:Memory Disorders / Q000188:drug therapy* / Q000378:metabolism*; D018697:Nootropic Agents / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology; D017208:Rats, Wistar; D043884:Receptor, Cannabinoid, CB1 / Q000819:agonists* / Q000037:antagonists & inhibitors / Q000378:metabolism; D012601:Scopolamine
chemical_list: D001095:Arachidonic Acids; D063386:Cannabinoid Receptor Agonists; D063387:Cannabinoid Receptor Antagonists; C543264:Cnr1 protein, rat; D063388:Endocannabinoids; D018697:Nootropic Agents; D010880:Piperidines; D011720:Pyrazoles; D043884:Receptor, Cannabinoid, CB1; C119324:arachidonylcyclopropylamide; C103505:AM 251; D012601:Scopolamine
keywords: Basolateral amygdala; Endocannabinoid system; Passive avoidance task; Rat(s); Scopolamine