RESUMO
OBJECTIVES: We studied the effects of ethyl acetate fraction (EAcF) obtained from Erythrina velutina leaves on mammalian myocardium. METHODS: The effect of EAcF on the contractility was studied using guinea-pig left atria mounted in a tissue bath (Tyrode's solution, 29°C, 95% CO2 , 5% O2 ) and electrically stimulated (1 Hz). Concentration-response curves of EAcF were obtained in the presence of propranolol (1 µm), nifedipine (1 µm) and in reserpinized animals (5 mg/kg). The involvement of l-type calcium current (ICa,L ) on the EAcF effect was observed in cardiomyocytes of mice assessed using patch-clamp technique. KEY FINDINGS: EAcF (550 µg/ml) had a positive inotropic effect, increasing the atrial force by 164% (EC50 = 157 ± 44 µg/ml, n = 6), but it was less potent than isoproterenol (EC50 = 0.0036 ± 0.0019 µg/ml, n = 8). The response evoked by EAcF was abolished by propranolol or nifedipine. Reserpine did not alter the inotropic response of EAcF. Furthermore, an enhancement of the ICa,L peak (31.2%) with EAcF was observed. Chemical analysis of EAcF revealed the presence of at least 10 different flavonoid glycoside derivatives. Two were identified as vicenin II and isorhoifolin. CONCLUSIONS: We conclude that EAcF increases the cardiac contractile force by increasing the l-type calcium current and activating the adrenergic receptor pathway.
Assuntos
Acetatos/química , Cardiotônicos/farmacologia , Erythrina/química , Átrios do Coração/efeitos dos fármacos , Coração/efeitos dos fármacos , Receptores Adrenérgicos/metabolismo , Animais , Cálcio/metabolismo , Catecolaminas/metabolismo , Feminino , Cobaias , Átrios do Coração/metabolismo , Isoproterenol/farmacologia , Masculino , Mamíferos/metabolismo , Contração Muscular/efeitos dos fármacos , Miocárdio/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/químicaRESUMO
Sideroxylon obtusifolium (Humb. ex Roem. & Schult.) T.D. Penn., Sapotaceae, is a plant with analgesic and anti-inflammatory activities used in folk medicine. In order to evaluate the actions of this plant, studies were performed on antinociceptive and anti-inflammatory activities with the ethanol extract (EE) of inner bark (100-400 mg/kg). Oral treatment with the EE elicited inhibitory activity (200 and 400 mg/kg, p<0.01) on acetic acid effect and reduced (100, 200, and 400 mg/kg, p<0.001) the formalin effect at the second-phase, however it did not elicit any inhibitory effect on hot-plate test. Carrageenan-induced oedema formation and leukocyte migration into the peritoneal cavity were reduced with the EE at 100, 200, and 400 mg/kg (p<0.001). In conclusion, the EE of Sideroxylon obtusifolium shows antinociceptive and anti-inflammatory activities, supporting the folkloric usage of the plant to treat pain and various inflammatory diseases.
A Sideroxylon obtusifolium (Humb. ex Roem. & Schult.) T.D. Penn., Sapotaceae, é utilizada na medicina popular em processos dolorosos e inflamatórios. Para avaliar as atividades analgésica e anti-inflamatória desta planta, estudos foram realizados com o extrato etanólico (EE) da entrecasca (100-400 mg/kg). O tratamento oral único dos animais com o EE inibiu (200 e 400 mg/kg, p<0,01) o efeito do ácido acético e reduziu (100, 200 e 400 mg/kg, p<0,001) o efeito da formalina na segunda fase; entretanto, não apresentou efeito no teste da placa quente. A formação de edema e a migração de leucócitos para a cavidade peritoneal induzidas pela carragenina foram reduzidas pelo tratamento com o EE (100, 200 e 400 mg/kg, p<0,001). Desta forma conclui-se que o EE da Sideroxylon obtusifolium apresenta atividades antinociceptiva e anti-inflamatória, suportando seu uso popular no tratamento da dor e de doenças inflamatórias.
RESUMO
Maytenus rigida Mart (Celastraceae), conhecida por "Bom-homem", "Bom-nome", "Cabelo-de-negro", "Casca-grossa" e "Pau-de-colher", é uma arvore de pequeno porte. A entrecasca do caule é empregada popularmente no Nordeste do Brasil no tratamento das dores em geral, infecções e inflamações. O presente trabalho avaliou tanto o perfil fitoquímico de M. rigida por meio de um roteiro analítico, quanto à atividade antibiótica dos extratos pelo método de Kirby-Bauer modificado. Os resultados demonstraram que os extratos etanólico, aquoso, clorofórmico, acetato de etila e hidroalcoólico de M. rigida apresentam atividade antibacteriana contra Escherichia coli, Pseudomonas aeruginosa e Staphylococcus aureus, enquanto que a fração hexânica não exibe qualquer atividade. Catequinas, quinonas, esteróides, triterpenos, saponinas, flavonóides e compostos fenólicos foram detectados na análise fitoquímica.
Maynetus rigida Mart (Celastraceae), known as "Bom-homem", "Bom-nome", "Cabelo-de-negro", "Casca-grossa" and "Pau-de-colher", is a small tree. The stem bark is used by the population in the northeast of Brazil to treat aches, infections and inflammations in general. The present work evaluated both the phytochemistry of M. rigida Mart by an analytical routine, and the antimicrobial activity of the bark extracts by the Kirby-Bauer modified method. Our results showed the aqueous, methanol, chloroform, ethyl acetate and hydroalcoolic extracts of M. rigida Mart has antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus, while the hexane extract does not have any activity. Catechins, quinones, steroids, triterpenes, saponins, flavonoids and phenolic compounds were detected by the phytochemical analysis.