RESUMO
The effects of acclimatization to middle attitude hypoxia on the resistance to acute emotional stress were studied on the model of posttraumatic stress disorder in rats. Anxyolitic, but not anxiogenic effect was observed in acclimatized rats. However, acclimatized rats with posttraumatic stress disorder were characterized by hypofunction of the pituitary-adrenocortical axis, which is typical of this pathology, and reduction in corticosterone/dehydroepiandrosterone ratio. At the neuroendocrine level, up-regulation of glucocorticoid receptors and a decrease in the level of corticotropin-releasing hormone in the hippocampus were revealed. The observed modifications of regulatory mechanisms can underlie hypofunction of the pituitary-adrenocortical axis. It was concluded that acclimatization to middle attitude hypoxia masks behavioral symptoms of posttraumatic stress disorder, but does not alter its pathogenetic neuroendocrine mechanisms.
Assuntos
Aclimatação/fisiologia , Doença da Altitude , Mascaramento Perceptivo/fisiologia , Transtornos de Estresse Pós-Traumáticos , Estresse Psicológico , Altitude , Doença da Altitude/fisiopatologia , Doença da Altitude/psicologia , Animais , Corticosterona/metabolismo , Modelos Animais de Doenças , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipotálamo-Hipofisário/fisiopatologia , Hipóxia/etiologia , Hipóxia/fisiopatologia , Hipóxia/psicologia , Masculino , Sistema Hipófise-Suprarrenal/metabolismo , Sistema Hipófise-Suprarrenal/fisiopatologia , Ratos , Ratos Wistar , Transdução de Sinais/fisiologia , Transtornos de Estresse Pós-Traumáticos/patologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologiaRESUMO
AIM: To assess antidepressant properties of remote ischemic limb pre- and post-conditioning. MATERIAL AND METHODS: The study was performed with rats that were subjected to unavoidable aversive stress in the 'learned helplessness' paradigm for developing experimental depression, or were additional exposed to three brief episodes of ischemia/reperfusion of the limb before or after stressing. RESULTS: Remote ischemic preconditioning completely prevented depressive-like behavior and caused hyperactivation of the pituitary-adrenal hormonal axis. Ischemic post-conditioning did not completely correct post-stress hormone dysregulation and animal stress-reactivity. CONCLUSION: Remote ischemic pre- and post-conditioning has a pronounced antidepressant effect and prevents the formation of the main behavioral and endocrine signs of experimental depression.