title: Early poststroke experience differentially alters periinfarct layer II and III cortex.
abstract: Early poststroke rehabilitation effectively improves recovery of function, likely by engaging multiple plasticity processes through use-dependent activation of neural circuits. The loci of such neuroplastic reorganization have not been examined during the initial phase of behavioral recovery. In the current study, we sought to evaluate sub-components of rehabilitation and to identify brain sites first engaged by early rehabilitation. Rats were subjected to endothelin-1 ischemia and placed in either enriched environment (EE), daily reach training (RT), combination of enriched environment and reach training (ER), or standard housing (ST) starting 7 days post ischemia. Functional and histopathological assessments were made after 2, 5, and 10 days of treatment. Animals exposed to 10 days of ER treatment exhibited significantly more use-dependent neuronal activity (FosB/ΔFosB expression) in perilesional cortex than those exposed to EE, RT, or ST treatments. Similar trends were observed in both perilesional striatum and contralesional forelimb motor cortex. This use-dependent plasticity was not explained by differences in neuronal death, inflammation, or lesion volume. The increased activity likely contributes to the neuroplastic changes and functional recovery observed after extended periods of rehabilitation. Importantly, EE or RT alone did not lead to enhanced activity suggesting that combination therapy is necessary to promote maximum recovery.
authors.affiliation: 1] BioMedical Sciences, Faculty of Medicine, Memorial University, St John's, Newfoundland and Labrador, Canada [2] Heart and Stroke Foundation Centre for Stroke Recovery, Ottawa, Ontario, Canada.
authors.forename: Jared
authors.initials: J
authors.lastname: Clarke
authors.affiliation: 1] BioMedical Sciences, Faculty of Medicine, Memorial University, St John's, Newfoundland and Labrador, Canada [2] Heart and Stroke Foundation Centre for Stroke Recovery, Ottawa, Ontario, Canada.
authors.forename: Kristopher D
authors.initials: KD
authors.lastname: Langdon
authors.affiliation: 1] BioMedical Sciences, Faculty of Medicine, Memorial University, St John's, Newfoundland and Labrador, Canada [2] Heart and Stroke Foundation Centre for Stroke Recovery, Ottawa, Ontario, Canada [3] Department of Cellular & Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada [4] Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Dale
authors.initials: D
authors.lastname: Corbett
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D008297:Male; D009044:Motor Cortex / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D009046:Motor Neurons / Q000378:metabolism / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function; D020521:Stroke / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D000071939:Stroke Rehabilitation; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: C483820:Fosb protein, rat; D016760:Proto-Oncogene Proteins c-fos