Inotropic effect of Citrus sinensis (L.) Osbeck leaf extracts on the guinea pig atrium

Oliveira, Evaleide Diniz de; Leite, Thais Serafim; Silva, Bagnolia Araujo da; Conde Garcia, Eduardo Antonio

Use este identificador para citar ou linkar para este item: https://ri.ufs.br/jspui/handle/riufs/20406

Registro completo de metadados

Campo DC	Valor	Idioma
dc.contributor.author	Oliveira, Evaleide Diniz de	-
dc.contributor.author	Leite, Thais Serafim	-
dc.contributor.author	Silva, Bagnolia Araujo da	-
dc.contributor.author	Conde Garcia, Eduardo Antonio	-
dc.date.accessioned	2024-11-08T12:27:58Z	-
dc.date.available	2024-11-08T12:27:58Z	-
dc.date.issued	2005	-
dc.identifier.citation	OLIVEIRA, E. D. Inotropic effect of Citrus sinensis (L.) Osbeck leaf extracts on the guinea pig atrium. Brazilian Journal of Medical and Biological Research, Ribeirão Preto, v. 38, n. 1, p. 111-118, jan. 2005. Disponível em: https://www.scielo.br/j/bjmbr/a/rj4kMmfWBWvkjdYFcwJyRZR/?format=pdf&lang=en. Acesso em: 8 nov. 2024.	pt_BR
dc.identifier.issn	0100-879X	-
dc.identifier.issn	1414-431X	-
dc.identifier.uri	https://ri.ufs.br/jspui/handle/riufs/20406	-
dc.language	eng	pt_BR
dc.publisher	Associação Brasileira de Divulgação Científica	pt_BR
dc.relation.ispartof	Brazilian Journal of Medical and Biological Research	pt_BR
dc.subject	Citrus sinensis	por
dc.subject	Contractility	por
dc.subject	Heart	por
dc.subject	Myocardium	por
dc.subject	Woodworth phenomenon	por
dc.subject	Coração	por
dc.subject	Miocárdio	por
dc.title	Inotropic effect of Citrus sinensis (L.) Osbeck leaf extracts on the guinea pig atrium	pt_BR
dc.type	Artigo	pt_BR
dc.identifier.license	Creative Commons Atribuição 4.0 Internacional (CC BY 4.0)	pt_BR
dc.description.resumo	The objective of the present investigation was to determine the contractile effect of crude and acetone leaf extracts of Citrus sinensis (L.) Osb. on mammalian myocardium. Crude leaf extracts have been used in folk medicine to treat neurological disorders. Some flavonoids isolated from this plant presented a positive inotropic effect on myocardium. This motivated us to test the extracts on the atria of guinea pigs of both sexes (300-500 g) and surprisingly we observed inotropic depression instead of an increase in force. The maximum effect of the crude extract was 79.4 ± 8.1% of the control force amplitude (N = 5 hearts, 10 trials, 27 ± 0.1ºC, stimulus: 2 Hz, 400 V, 0.5 ms). The EC50 for crude, ethanol, acetic, aqueous, and acetone extracts was 300, 300, 600, 1000, and 140 µg/ml, respectively, with a Hill constant of 1.8, 2.0, 2.5, 2.0, and 1.4, respectively. Blockade of cholinergic, beta-adrenergic, or opioid membrane receptors with 1.5 µM atropine sulfate, 1 µM propranolol, and 10 µM naloxone, respectively, did not change the effect of the crude extract. The acetone extract abolished the Bowditch positive staircase phenomenon (N = 5 hearts, 10 trials, 27 ± 0.1ºC), suggesting a possible reduction of the calcium inward current, and also promoted the so-called Woodworth phenomenon. The effect was concentration-dependent and indicated the existence of another inhibitory contractile mechanism such as the simultaneous activation of some of the membrane potassium channels reducing the myocardial action potential duration and further decreasing the cellular calcium entry.	pt_BR
dc.description.local	Ribeirão Preto	pt_BR
Aparece nas coleções:	DFS - Artigos de periódicos

Arquivos associados a este item:

Arquivo	Descrição	Tamanho	Formato
InotropicEffectCitrusSinensis.pdf		631,72 kB	Adobe PDF	Visualizar/Abrir

Mostrar registro simples do item Visualizar estatísticas