title: Impaired water maze learning performance in mu-opioid receptor knockout mice.
abstract: Previous study has demonstrated that the lack of mu-opioid receptor decreased LTP in the dentate gyrus of the hippocampus, suggesting the possibility that the lack of mu-opioid receptor may accompany a change in learning and memory. However, no behavioral study has been undertaken to correlate LTP deficits with spatial memory impairment in mu-opioid receptor knockout mice. Therefore, the present study investigated the hypothesis that mu-opioid receptors contribute to learning and memory by using the Morris water maze, and comparing responses in wild type and mu-opioid receptor gene knockout mice. Our results indicated that mu-opioid receptor knockout mice showed a significant spatial memory impairment compared to wild type in the Morris water maze. This result suggests that the expression of mu-opioid receptor plays an important role in spatial learning and memory examined by Morris water maze.
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D018782:Maze Learning / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout / Q000502:physiology*; D009043:Motor Activity / Q000502:physiology; D011930:Reaction Time; D017450:Receptors, Opioid, mu / Q000235:genetics / Q000502:physiology*; D013037:Spatial Behavior / Q000502:physiology
chemical_list: D017450:Receptors, Opioid, mu