RESUMO
Increased production of reactive oxygen species (ROS) has been linked to the pathogenesis of congestive heart failure. However, emerging evidence suggests the involvement of ROS in the regulation of various physiological cellular processes in the myocardium. In this review, we summarize the latest findings regarding the role of ROS in the acute regulation of cardiac contractility. We discuss ROS-dependent modulation of the inotropic responses to G protein-coupled receptor agonists (e.g. ß-adrenergic receptor agonists and endothelin-1), the potential cellular sources of ROS (e.g. NAD(P)H oxidases and mitochondria) and the proposed end-targets and signalling pathways by which ROS affect contractility. Accumulating new data supports the fundamental role of endogenously generated ROS to regulate cardiac function under physiological conditions.
Assuntos
Coração/fisiologia , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Endotelina-1/metabolismo , Humanos , Receptores Adrenérgicos beta/metabolismo , Transdução de Sinais/fisiologiaRESUMO
The effect of Ca-antagonist, long-acting verapamil and the selective beta-1 blocking bisoprolol were investigated and compared in the secondary prevention after myocardial infarction. Eighty-seven patients were enrolled, 27 patients were not included because of the exclusion criteria, 30 patients were treated with verapamil and 30 patients with bisoprolol. During the 540 days of follow up period treadmill ergometry and dobutamine stress-test with SPECT investigation were performed two times. Both clinically and the data of our investigations the effect of the two drugs in the secondary prevention was good, and even at the 540th day the protective effect was still excellent.
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Bisoprolol/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Infarto do Miocárdio/prevenção & controle , Verapamil/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológicoRESUMO
The authors review the different methodological suggestions concerning thrombolysis, especially from the aspects of the absolute and relative contraindications of the treatment. They present case reports to prove that in patients with life threatening thromboembolic diseases some points of contraindications may be disregarded. They suggest a new strategy of absolute and relative contraindications be made considering the currently available recently introduced thrombolytic therapy.
