title: Environmental enrichment as a therapeutic avenue for anxiety in aged Wistar rats: Effect on cat odor exposition and GABAergic interneurons.
abstract: The use of more ethological animal models to study the neurobiology of anxiety has increased in recent years. We assessed the effect of an environmental enrichment (EE) protocol (24h/day over a period of two months) on anxiety-related behaviors when aged Wistar rats (21months old) were confronted with cat odor stimuli. Owing to the relationship between GABAergic interneurons and the anxiety-related neuronal network, we examined changes in the expression of Parvalbumin (PV) and 67kDa form of glutamic acid decarboxylase (GAD-67) immunoreactive cells in different brain regions involved in stress response. Behavioral results revealed that enriched rats traveled further and made more grooming behaviors during the habituation session. In the cat odor session, they traveled longer distances and they showed more active interaction with the odor stimuli and less time in freezing behavior. Zone analysis revealed that the enriched group spent more time in the intermediate zone according to the proximity of the predator odor. Regarding the neurobiological data, the EE increased the expression of PV-positive cells in some medial prefrontal regions (cingulate (Cg) and prelimbic (PL) cortices), whereas the GAD-67 expression in the basolateral amygdala was reduced in the enriched group. Our results suggest that EE is able to reduce anxiety-like behaviors in aged animals even when ethologically relevant stimuli are used. Moreover, GABAergic interneurons could be involved in mediating this resilient behavior.
authors.affiliation: Departamento de Psicología Biológica y de la Salud, Facultad de Psicología, Universidad Autónoma de Madrid, Ciudad Universitaria de Cantoblanco s/n, 28049 Madrid, Spain. Electronic address: patricia.sampedro@uam.es.
authors.forename: P
authors.initials: P
authors.lastname: Sampedro-Piquero
authors.affiliation: Unidad de Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario Carlos Haya de Málaga, E-29010 Málaga, Spain. Electronic address: estela.castilla@ibima.eu.
authors.forename: E
authors.initials: E
authors.lastname: Castilla-Ortega
authors.affiliation: Laboratorio de Neurociencias, Departamento de Psicología, Universidad de Oviedo, plaza Feijoo s/n, 33003 Oviedo, Spain; Instituto de Neurociencias del Principado de Asturias (INEUROPA), Spain. Electronic address: zancadaclara.uo@uniovi.es.
authors.forename: C
authors.initials: C
authors.lastname: Zancada-Menendez
authors.affiliation: Departamento de Psicobiología y Metodología de las Ciencias del Comportamiento, Instituto de Investigación Biomédica de Málaga (IBIMA), Facultad de Psicología, Universidad de Málaga, Spain. Electronic address: luis@uma.es.
authors.forename: L J
authors.initials: LJ
authors.lastname: Santín
authors.affiliation: Laboratorio de Neurociencias, Departamento de Psicología, Universidad de Oviedo, plaza Feijoo s/n, 33003 Oviedo, Spain; Instituto de Neurociencias del Principado de Asturias (INEUROPA), Spain. Electronic address: begega@uniovi.es.
authors.forename: A
authors.initials: A
authors.lastname: Begega
mesh_terms: D000375:Aging / Q000473:pathology / Q000502:physiology / Q000523:psychology*; D000818:Animals; D001007:Anxiety / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D002415:Cats; D004777:Environment; D005106:Exploratory Behavior / Q000502:physiology; D059330:GABAergic Neurons / Q000473:pathology / Q000502:physiology*; D005968:Glutamate Decarboxylase / Q000378:metabolism; D006120:Grooming / Q000502:physiology; D006799:Housing, Animal; D007150:Immunohistochemistry; D007395:Interneurons / Q000473:pathology / Q000502:physiology*; D023421:Models, Animal; D009812:Odorants; D010320:Parvalbumins / Q000378:metabolism; D010812:Physical Stimulation; D011235:Predatory Behavior; D017208:Rats, Wistar; D055500:Resilience, Psychological
chemical_list: D010320:Parvalbumins; D005968:Glutamate Decarboxylase; C402565:glutamate decarboxylase 1
keywords: GABA; Parvalbumin; Wistar rat; aging; cat odor; environmental enrichment