Influência do sistema renina angiotensina na modulação do estado redox, no balanço autonômico e na hipertrofia cardíaca induzida pelo hipertireoidismo experimental
AUTOR(ES)
Dhãniel Dias Baraldi
FONTE
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia
DATA DE PUBLICAÇÃO
2012
RESUMO
Hyperthyroidism is an epidemiologic relevant pathology, which substantially affects the cardiovascular system. The hyperthyroid state may affect basal metabolism, O2 cell consumption, renin-angiotensin system, and increase reactive oxygen species production. Those alterations produce morphological, biochemical, functional and molecular consequences in cardiac tissue. Hyperthyroidism induced cardiac hypertrophy develops due to a set of events, which signals cell survival and proliferation, including reactive oxygen species, cardiac rennin-angiotensin system, and autonomic nervous system. In the present study, the role of cardiac renin-angiotensin system on development of hyperthyroidism induced cardiac hypertrophy, and the involvement of autonomic nervous system and reactive oxygen species, were assessed trough blockade of angiotensin II receptor AT1. For that, were used male Wistar rats, weighting about 220g, divided in 4 experimental groups,: Control (C), Losartan (L) (10mg/Kg body weight/day, 28 days, intragastric probe), T4 (12mg/L L-thyroxin in drinking water, 28 days), and T4+L. Cardiac mass, spectral analysis (autonomic balance), hydrogen peroxide (H2O2), and myocardial protein expression of angiotensin II receptor (AT1), NADPH oxidase, Nrf-2, and heme-oxygenase-1 (HO-1), were quantified. Cardiac hypertrophy and autonomic umbalance induced by thyroid hormones were attenuated in the T4+losartan group. The H2O2, as well as Nrf-2, gp91phox, AT1 and HO-1 immunocontent were elevated in T4 group. All these effects were attenuated by losartan, except AT1 levels. The overall results suggest that blockade of AT1 receptor lead to relevant impact on autonomic balance and cardiac hypertrophy, being ROS and Nrf-2/ HO-1 system possible mediators in this alterations in experimental hyperthyroidism.
ASSUNTO(S)
hipertireoidismo losartan hipertrofia cardíaca renin-angiotensin system hormônios tireóideos heme-oxygenase thyroid hormones sistema renina-angiotensina cardiac hypertrophy losartan spectral analysis espécies reativas de oxigênio reactive oxygen species modelos animais de doenças
ACESSO AO ARTIGO
http://hdl.handle.net/10183/54943Documentos Relacionados
- Influência do estresse oxidativo no desenvolvimento da hipertrofia e insuficiência cardíaca induzida pelo hipertireoidismo em ratos
- ROLE OF THE RENIN-ANGIOTENSIN SYSTEM IN RESISTANCE EXERCISE-INDUCED CARDIAC HYPERTROPHY
- Hipertrofia cardíaca induzida pelo hipertireoidismo experimental : papel do estado redox sobre proteínas envolvidas em vias de sinalização intracelular para crescimento, sobrevivência e morte celular
- Disfunção renal induzida por modelo polimicrobiano de Sepse: avaliação de componentes do sistema renina-angiotensina
- O bloqueio do sistema renina-angiotensina atenua a remodelação cardíaca de ratos submetidos a estenose aórtica