Antispasmodic effect of Jatropha gossypiifolia is mediated through dual blockade of muscarinic receptors and Ca2+ channels
AUTOR(ES)
Silva, Selma do N., Abreu, Iracelle C., Freire, Sônia Maria de F., Cartágenes, Maria do Socorro de S., Ribeiro, Rachel M., Castro, Ahirlan S. de, Borges, Antônio C. R., Borges, Marilene O. da R.
FONTE
Revista Brasileira de Farmacognosia
DATA DE PUBLICAÇÃO
29/07/2011
RESUMO
The antispasmodic activity of Jatropha gossypiifolia L., Euphorbiaceae, aerial parts was investigated in rodents using the mouse intestinal transit model and acetylcholine (ACh, 10-9 to 10-4 M) and calcium (CaCl2, 10-4 to 10-1 M)-induced contractions of isolated rat jejunum. Similar to atropine (1 mg/kg), oral doses of ethanolic extract (EE) of J. gossypiifolia (500, 1000 and 2000 mg/kg) produced a decrease in intestinal transit (37.6 to 57.1%) when compared with control. The ACh-induced contraction in the jejunum was inhibited by EE (0.5, 1.0 and 2.0 mg/mL), chloroformic (CF) and aqueous fractions (0.1 and 0.5 mg/mL) and methanolic subfraction (0.05 and 0.25 mg/mL), suggesting an antimuscarinic mechanism. CaCl2 - induced responses in jejunum were also attenuated in the presence of CF (0.05 and 0.1 mg/mL) implying a direct interference of CF with the influx of calcium ions in the cells. Only the organic fraction of the extract had a calcium-antagonist effect, whereas both chloroformic and aqueous fractions had anticholinergic effect. These results suggest that the antispasmodic effect of J. gossypiifolia may be due a combination of anticholinergic and calcium antagonist mechanisms.
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