Activation of septal 5-HT1A receptors alters spatial memory encoding, interferes with consolidation, but does not affect retrieval in rats subjected to a water-maze task.

摘要: Using Long-Evans rats tested in a water maze, this study assessed the role of 5-HT1A/5-HT7 receptors medial septum encoding, consolidation, and retrieval spatial information. The testing protocol (acquisition: daily four-trial sessions over three consecutive days; retention: probe trial on day 4) was first validated by showing that intraseptal infusions lidocaine (LIDO; 40 μg/0.5 μL) disrupted acquisition task. 8-OH-DPAT (4 infused before each session prevented learning/retention platform location, an effect attenuated pretreatment with 5-HT1A receptor antagonist WAY 100635. With 5-HT7 SB 269970, 8-OH-DPAT-induced deficit seemed attenuated, but there no subsequent retention. When immediately, 1, 4, or 6 h after session, did not hinder consolidation. were performed 2 postacquisition, however, consolidation disrupted. Finally, when drug-free acquisition, had effect, suggesting interference processes. We also established effects visible, altered neither home-cage activity nor anxiety-related behavior (elevated plus-maze). Altogether, these results show septal region contribute both to declarative-like information encoding subsequently, within given postacquisition time window, its They do participate recently learned These observations suggest serotonin-mediated mechanism involved hippocampal- dependent knowledge. might have some relevance approaches aimed at modifying serotonergic functions brain for treatment disorders such as depression, anxiety, post-traumatic stress, amnesia. © 2007 Wiley-Liss, Inc.