Orexin knockout mice exhibit impaired spatial working memory.
Orexins play a crucial role in the maintenance of arousal and are involved in the modulation of diverse physiological process, including cognitive function. Recent data have suggested that orexins are involved in learning and memory processes. The purpose of this study was to assess the effects of orexin deficiency on working memory. A delayed non-matching-to-place T-maze task was used to evaluate spatial working memory in mice lacking orexin prepro-peptide (orexin knockout; KO) and wild-type controls. We demonstrated that the number of correct choices in the orexin KO mice became lower than that of the controls over training. In an object exploration task, the controls explored the displaced object more than the mutants did, whereas this difference was not observed for the nondisplaced objects in either group. The orexin KO mice showed locomotor activity comparable to the control mice in terms of total distance traveled across training in both the object exploration task and the open field test. These findings indicate that the orexin system plays an important role in working memory of spatial cues.
['Dang|Ruozhi|R|', 'Chen|Qiuhan|Q|', 'Song|Jie|J|', 'He|Chao|C|', 'Zhang|Jun|J|', 'Xia|Jianxia|J|', 'Hu|Zhian|Z|']
D000818:Animals D001522:Behavior, Animal D001921:Brain D060825:Cognitive Dysfunction D018782:Maze Learning D008570:Memory, Short-Term D051379:Mice D018345:Mice, Knockout D009043:Motor Activity D000068797:Orexins D065852:Spatial Memory
Spatial working memory Cognitive function Locomotor activity Orexin/hypocretin