title: Neuronal Activation After Prolonged Immobilization: Do the Same or Different Neurons Respond to a Novel Stressor?
abstract: Despite extensive research on the impact of emotional stressors on brain function using immediate-early genes (e.g., c-fos), there are still important questions that remain unanswered such as the reason for the progressive decline of c-fos expression in response to prolonged stress and the neuronal populations activated by different stressors. This study tackles these 2 questions by evaluating c-fos expression in response to 2 different emotional stressors applied sequentially, and performing a fluorescent double labeling of c-Fos protein and c-fos mRNA on stress-related brain areas. Results were complemented with the assessment of the hypothalamic-pituitary-adrenal axis activation. We showed that the progressive decline of c-fos expression could be related to 2 differing mechanisms involving either transcriptional repression or changes in stimulatory inputs. Moreover, the neuronal populations that respond to the different stressors appear to be predominantly separated in high-level processing areas (e.g., medial prefrontal cortex). However, in low-hierarchy areas (e.g., paraventricular nucleus of the hypothalamus) neuronal populations appear to respond unspecifically. The data suggest that the distinct physiological and behavioral consequences of emotional stressors, and their implication in the development of psychopathologies, are likely to be closely associated with neuronal populations specifically activated by each stressor.
authors.affiliation: Institut de Neurociències, CIBERSAM and Red de Transtornos Adictivos (RTA), Unitat de Fisiologia Animal (Facultat de Biociéncies), Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.|Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Marín-Blasco
authors.affiliation: Institut de Neurociències, CIBERSAM and Red de Transtornos Adictivos (RTA), Unitat de Fisiologia Animal (Facultat de Biociéncies), Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Muñoz-Abellán
authors.affiliation: Institut de Neurociències, CIBERSAM and Red de Transtornos Adictivos (RTA), Unitat de Fisiologia Animal (Facultat de Biociéncies), Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.|Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, MA 02478, USA.|Unitat de Psicobiologia (Facultat de Psicologia), Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
authors.forename: Raül
authors.initials: R
authors.lastname: Andero
authors.affiliation: Institut de Neurociències, CIBERSAM and Red de Transtornos Adictivos (RTA), Unitat de Fisiologia Animal (Facultat de Biociéncies), Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.|Unitat de Psicobiologia (Facultat de Psicologia), Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
authors.forename: Roser
authors.initials: R
authors.lastname: Nadal
authors.affiliation: Institut de Neurociències, CIBERSAM and Red de Transtornos Adictivos (RTA), Unitat de Fisiologia Animal (Facultat de Biociéncies), Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Armario
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000033:anatomy & histology / Q000166:cytology* / Q000378:metabolism; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology*; D008297:Male; D009474:Neurons / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D017207:Rats, Sprague-Dawley; D013312:Stress, Physiological / Q000502:physiology*; D013997:Time Factors
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone