Vias de sinalização endotelial α2, AT1, e AT2 sobre a reatividade da aorta de ratos após consumo de etanol e exposição ao estresse, isoladamente e em associação

• Autor(a) principal: Baptista, Rafaela de Fátima Ferreira [UNESP]
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/123759; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/12-06-2015/000830123.pdf
• topic: Stress (Fisiologia); Etanol - Consumo; Endotelio; Sistema cardiovascular - Doenças; Receptores adrenérgicos; Cardiovascular system - Diseases

Introduction: stress and ethanol consumption are important cardiovascular risk factors. Objectives: to evaluate the effects of stress exposure and ethanol consumption, alone and in association on blood pressure and thoracic aorta reactivity in vitro. Methods: Wistar adult male rats (8-10 per group) were separated into groups: control, ethanol (20% ethanol in their drinking water for 6 weeks), stress (restraint 1h/day 5 days/week for 6 weeks) ethanol/stress (both procedures in association). Caudal systolic blood pressure (SBP), plasma corticosterone and plasma antioxidant capacity were evaluated. Concentrationeffect curves to noradrenaline in the absence or presence of yohimbine (α2- blocker), L-NAME (inhibitor of nitric oxide synthase) or indomethacin (cyclooxygenase inhibitor); phenylephrine; and angiotensin II in the absence and presence of losartan (AT1-blocker), PD123-319 (AT2-blocker), L-NAME or indomethacin were obtained from the intact and denuded-endothelium aortas. 50% effective concentration (EC50) and maximum response (MR) were compared between groups using MANOVA/Tukey. P < 0.05 was considered statistically significant. Results: exposure to stress, alone and in association with ethanol consumption increased SBP. Stress and stress in association increased the MR to noradrenaline in intact aortas. This hyperreactivity was abolished by both removal of the endothelium and the presence of indomethacin or yohimbine, but was not changed by the presence of L-NAME. In turn, the consumption of ethanol alone did not alter the reactivity to noradrenaline. Responses to phenylephrine in aortas with and without endothelium and to noradrenaline in aortas without endothelium remained unchanged regardless of protocol. Ethanol and stress, alone and in association, did not alter the reactivity of intact aorta to angiotensin II. PD123-319 decreased MR to angiotensin II in intact rat aortas of ethanol and ethanol/stress groups compared to the ...