title: A Golgi-Cox morphological analysis of neuronal changes induced by environmental enrichment.
abstract: Exposure to an enriched environment (EE), consisting of a combination of increased exercise, social interactions and learning, has been shown to produce many positive effects in the CNS. In this study, we use a Golgi-Cox analysis to examine and dissect the role of various components of the enriched environment on two measures of neuronal growth: total cell volume and total dendritic length in four regions of the brain. In the hippocampus, CA1 and dentate gyrus cells, animals raised in an enriched environment demonstrate significant morphological change. These changes were not observed in layer V pyramidal neurons of the cerebral cortex or spiny neurons located in the striatum. To determine if one or more of the individual components of the EE were responsible for the changes in neuronal morphology, we examined mice raised with free access to exercise wheels. In these mice, no morphological changes were observed. These results suggest that changes in the CA1 and dentate gyrus morphology were a result of alterations in the animal's environment and not an increase in motor activity.
authors.affiliation: Department of Developmental Neurobiology, Saint Jude Children's Research Hospital, 332 North Lauderdale, Memphis, TN 38105, USA.
authors.forename: Ciaran J
authors.initials: CJ
authors.lastname: Faherty
authors.forename: Dan
authors.initials: D
authors.lastname: Kerley
authors.forename: Richard Jay
authors.initials: RJ
authors.lastname: Smeyne
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002454:Cell Differentiation / Q000502:physiology*; D048429:Cell Size / Q000502:physiology; D002540:Cerebral Cortex / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D003712:Dendrites / Q000502:physiology / Q000648:ultrastructure*; D018891:Dentate Gyrus / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D004780:Environment, Controlled; D005106:Exploratory Behavior / Q000502:physiology; D006624:Hippocampus / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D008297:Male; D008627:Mercuric Chloride; D051379:Mice; D008810:Mice, Inbred C57BL; D017072:Neostriatum / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D010805:Physical Conditioning, Animal / Q000502:physiology; D011192:Potassium Dichromate; D012683:Sensory Deprivation / Q000502:physiology*; D012919:Social Behavior; D013687:Telencephalon / Q000166:cytology* / Q000254:growth & development* / Q000502:physiology
chemical_list: D008627:Mercuric Chloride; D011192:Potassium Dichromate