Use este identificador para citar ou linkar para este item: http://www.repositorio.ufop.br/handle/123456789/1813
Título: Baroreflex function in conscious rats submitted to iron overload.
Autor(es): Cardoso, Leonardo Máximo
Pedrosa, Maria Lúcia
Silva, Marcelo Eustáquio
Moraes, Márcio Flávio Dutra
Colombari, Eduardo
Chianca Júnior, Deoclécio Alves
Palavras-chave: Blood pressure
Deferoxamine
Iron dextran
Baroreflex
Iron overload
Heart rate
Data do documento: 2005
Referência: CARDOSO, L. M. et al. Baroreflex function in conscious rats submitted to iron overload. BBararozirleiaflne xJo aunrdn ailr oonf Moveedrilcoaald and Biological Research, v. 38, n.2, p.205-214, fev. 2005. Disponível em: http://www.scielo.br/pdf/bjmbr/v38n2/5462.pdf. Acesso em: 26 nov. 2012.
Resumo: Our hypothesis is that iron accumulated in tissue, rather than in serum, may compromise cardiovascular control. Male Fischer 344 rats weighing 180 to 220 g were divided into 2 groups. In the serum iron overload group (SIO, N = 12), 20 mg elemental iron was injected ip daily for 7 days. In the tissue iron overload group (TIO, N = 19), a smaller amount of elemental iron was injected (10 mg, daily) for 5 days followed by a resting period of 7 days. Reflex heart rate responses were elicited by iv injections of either phenylephrine (0.5 to 5.0 µg/kg) or sodium nitroprusside (1.0 to 10.0 µg/kg). Baroreflex curves were determined and fitted to sigmoidal equations and the baroreflex gain coefficient was evaluated. To evaluate the role of other than a direct effect of iron on tissue, acute treatment with the iron chelator deferoxamine (20 mg/kg, iv) was performed on the TIO group and the baroreflex was re-evaluated. At the end of the experiments, evaluation of iron levels in serum confirmed a pronounced overload for the SIO group (30-fold), in contrast to the TIO group (2-fold). Tissue levels of iron, however, were higher in the TIO group. The SIO protocol did not produce significant alterations in the baroreflex curve response, while the TIO protocol produced a nearly 2-fold increase in baroreflex gain (-4.34 ± 0.74 and -7.93 ± 1.08 bpm/mmHg, respectively). The TIO protocol animals treated with deferoxamine returned to sham levels of baroreflex gain (-3.7 ± 0.3 sham vs -3.6 ± 0.2 bpm/mmHg) 30 min after the injection. Our results indicate an effect of tissue iron overload on the enhancement of baroreflex sensitivity.
URI: http://www.repositorio.ufop.br/handle/123456789/1813
ISSN: 1414431X
Licença: No permission is required from the authors or the publishers download, reuse, reprint, modify, distribute, and/or copy articles published in the BJMBR, as long as the original authors and source are cited. Fonte: http://www.bjournal.com.br/index.php?option=com_content&view=article&id=185&Itemid=139 Acesso em: 21/01/2014
Aparece nas coleções:DECBI - Artigos publicados em periódicos

Arquivos associados a este item:
Arquivo Descrição TamanhoFormato 
ARTIGO_BaroreflexFunctionConscious.pdf484,14 kBAdobe PDFVisualizar/Abrir


Os itens no repositório estão protegidos por copyright, com todos os direitos reservados, salvo quando é indicado o contrário.