title: Forebrain mineralocorticoid receptor overexpression enhances memory, reduces anxiety and attenuates neuronal loss in cerebral ischaemia.
abstract: The nuclear mineralocorticoid receptor (MR), a high-affinity receptor for glucocorticoids, is highly expressed in the hippocampus where it underpins cognitive, behavioural and neuroendocrine regulation. Increased neuronal MR expression occurs early in the response to cellular injury in vivo and in vitro and is associated with enhanced neuronal survival. To determine whether increased neuronal MR might be causal in protecting against ischaemic damage in vivo we generated a forebrain-specific MR-overexpressing transgenic mouse (MR-Tg) under the control of the CamKII alpha promoter, and subjected mice to transient cerebral global ischaemia induced by bilateral common carotid artery occlusion for 20 min. We also separately assessed the effects of MR overexpression on hypothalamic-pituitary-adrenal (HPA) axis activity and cognitive and affective functions in noninjured animals. Our results showed that MR-Tg mice had significantly reduced neuronal death following transient cerebral global ischaemia compared to wild-type littermates. This effect was not associated with alterations in basal or poststress HPA axis function or in arterial blood pressure. MR-Tg mice also demonstrated improved spatial memory retention, reduced anxiety and altered behavioural response to novelty. The induction of neuronal MR appears to offer a protective response which has potential therapeutic implications in cerebral ischaemia and cognitive and affective disorders.
authors: Endocrinology Unit, Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, Edinburgh, UK. m.lai@ed.ac.uk
authors: Maggie
authors: M
authors: Lai
authors: Karen
authors: K
authors: Horsburgh
authors: Sung-Eun
authors: SE
authors: Bae
authors: Roderick N
authors: RN
authors: Carter
authors: Dirk J
authors: DJ
authors: Stenvers
authors: Jill H
authors: JH
authors: Fowler
authors: Joyce L
authors: JL
authors: Yau
authors: Celso E
authors: CE
authors: Gomez-Sanchez
authors: Megan C
authors: MC
authors: Holmes
authors: Christopher J
authors: CJ
authors: Kenyon
authors: Jonathan R
authors: JR
authors: Seckl
authors: Malcolm R
authors: MR
authors: Macleod
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001007:Anxiety / Q000503:physiopathology*; D001522:Behavior, Animal / Q000502:physiology; D002545:Brain Ischemia / Q000473:pathology / Q000503:physiopathology*; D016923:Cell Death / Q000502:physiology; D003345:Corticosterone; D005106:Exploratory Behavior / Q000502:physiology; D015870:Gene Expression / Q000235:genetics*; D018782:Maze Learning / Q000502:physiology; D008568:Memory / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D009474:Neurons / Q000473:pathology*; D016548:Prosencephalon / Q000166:cytology / Q000378:metabolism*; D011930:Reaction Time / Q000235:genetics; D018161:Receptors, Mineralocorticoid / Q000235:genetics / Q000502:physiology*; D012149:Restraint, Physical / Q000379:methods
chemical_list: D018161:Receptors, Mineralocorticoid; D003345:Corticosterone