title: Blunted hippocampal, but not striatal, acetylcholine efflux parallels learning impairment in diencephalic-lesioned rats.
abstract: A rodent model of diencephalic amnesia, pyrithiamine-induced thiamine deficiency (PTD), was used to investigate the dynamic role of hippocampal and striatal acetylcholine (ACh) efflux across acquisition of a nonmatching-to-position (NMTP) T-maze task. Changes in ACh efflux were measured in rats at different time points in the acquisition curve of the task (early=day 1, middle=day 5, and late=day 10). Overall, the control group had higher accuracy scores than the PTD group in the latter sessions of NMTP training. During the three microdialysis sampling points, all animals displayed significant increases in ACh efflux in both hippocampus and striatum, while performing the task. However, on day 10, the PTD group showed a significant behavioral impairment that paralleled their blunted hippocampal--but not striatal--ACh efflux during maze training. The results support selective diencephalic-hippocampal dysfunction in the PTD model. This diencephalic-hippocampal interaction appears to be critical for successful episodic and spatial learning/memory.
authors.affiliation: Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY 13902, USA.
authors.forename: Jessica J
authors.initials: JJ
authors.lastname: Roland
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Savage
mesh_terms: D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D004027:Diencephalon / Q000187:drug effects; D004195:Disease Models, Animal; D005106:Exploratory Behavior / Q000502:physiology; D006624:Hippocampus / Q000378:metabolism*; D020915:Korsakoff Syndrome / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D007859:Learning Disabilities / Q000378:metabolism*; D008297:Male; D018782:Maze Learning / Q000502:physiology*; D017551:Microdialysis; D017072:Neostriatum / Q000378:metabolism*; D009929:Organ Size; D011745:Pyrithiamine; D051381:Rats; D017207:Rats, Sprague-Dawley; D013788:Thalamus / Q000473:pathology; D013832:Thiamine Deficiency / Q000139:chemically induced
chemical_list: D011745:Pyrithiamine; D000109:Acetylcholine