Mapping of neuronal activation and CRH/AVP expression in rats deprived of paradoxical sleep: a neurobiological and comparative approach

• Grant number: 17/06419-4
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: August 28, 2017
• End date: August 27, 2018
• Field of knowledge: Biological Sciences - Pharmacology - Neuropsychopharmacology
• Principal Investigator: Deborah Suchecki
• Grantee: Danilo Alves de Moraes
• Supervisor: Gloria e Hoffman
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Institution abroad: Morgan State University (MSU), United States
• Associated to the scholarship: 14/22218-0 - Evaluation of stress responses induced by paradoxical sleep deprivation in rats Wistar: a neurobiological and comparative approach, BP.DR

Abstract

Stressors are responsible for generating a set of neuronal, endocrine, autonomic and behavioral responses, coordinated by the central nervous system (CNS). In rodents a number of findings demonstrate that paradoxical sleep deprivation (PSD) using the single platform method (SPM) triggers stress response. However, there is a recurrent criticism of these results, questioning whether these changes are due to the suppression of paradoxical sleep or other stressors associated to the method. Other methods of PSD produce stress responses similar to those described by the SPM, varying in magnitude, leading us to propose that prolonged, unremitting PSD, regardless of the method, is a stressful stimulus responsible for these changes. The sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenal (HPA) axis are the main physiologic stress response systems; however, another perspective to evaluate the stress response involves the perception of the stimulus by the brain, which is able to discriminate between physical or psychological stimuli and promote the activation of specific pathways. Thus, the objectives of this study are to map the neuronal activation (immunoreactivity for erk) and evaluate HPA axis stress response at the hypothalamic level (immunoreactivity for corticotropin releasing hormone - CRH - and arginine vasopressin - AVP) in animals submitted to SPM, comparing with other stress models: cold (physical stressor), predator odor (psychological stressor) and restraint stress (mixed physical and psychological stressor). The stimuli were applied for one or four days, in order to verify differences between the exposure time and the possible existence of habituation. (AU)