title: Effect of reversible inactivation of the reuniens nucleus on spatial learning and memory in rats using Morris water maze task.
abstract: The involvement of thalamic midline nuclei (MLN) in early stage of Alzheimer's disease and in diencephalic amnesia has drawn attention to the connectivity between the nucleus reuniens (RE) and structures of medial temporal lobe. RE is major source of thalamic afferents to the hippocampus and has been shown to exert powerful excitatory action on CA1 of hippocampus, which is supposed to be involved in learning and memory processes. However, the role of the RE on spatial memory is a controversial issue. The present study was designed to evaluate the role of the RE in acquisition, consolidation and retrieval of spatial reference memory (RM) and working memory (WM). We assessed the effect of reversible inactivation of RE with tetracaine (0.5 microl, 2%) on different stages of memory. Rats were trained on RM and WM versions of the Morris water maze (MWM) task. RE was inactivated before or immediately after training or before the probe trial of retrieval tests. The data showed that reversible inactivation of the RE significantly impaired both RM and WM versions of MWM. Therefore, it seems that nucleus reuniens of thalamus plays a role in spatial RM and WM version of the MWM task in rats.
authors.affiliation: Neuroscience Research Center and Department of Physiology, Faculty of medicine, Shahid Beheshti University (Medical Sciences), Tehran, Iran.
authors.forename: Farzaneh Ghiafeh
authors.initials: FG
authors.lastname: Davoodi
authors.forename: Fereshteh
authors.initials: F
authors.lastname: Motamedi
authors.forename: Nasser
authors.initials: N
authors.lastname: Naghdi
authors.forename: Esmaeil
authors.initials: E
authors.lastname: Akbari
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage / Q000633:toxicity; D000818:Animals; D004924:Escape Reaction / Q000502:physiology; D005106:Exploratory Behavior / Q000187:drug effects / Q000502:physiology; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology*; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D008845:Microinjections / Q000379:methods; D020644:Midline Thalamic Nuclei / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013037:Spatial Behavior / Q000187:drug effects / Q000502:physiology*; D013550:Swimming; D013748:Tetracaine / Q000008:administration & dosage / Q000633:toxicity; D013788:Thalamus / Q000166:cytology / Q000187:drug effects / Q000502:physiology
chemical_list: D000779:Anesthetics, Local; D013748:Tetracaine