| "Hydrastis or goldenseal, one of the most popular medicinal herbs in the U.S.A., is used in mild pathological conditions like cold and flu, based on the pharmacological properties of its active components, berberine (anticholinergic, antisecretory, and antimicrobial) and β-hydrastine (astringent). We previously reported the relaxant effect of a total ethanolic extract of hydrastis on carbachol precontracted isolated guinea pig trachea, and with the present study, using the same experimental model, we aimed at evaluating the contribution of its major alkaloids, berberine, β-hydrastine, canadine and canadaline to the total effect. Furthermore, using specific pharmacological tools, like timolol and xanthine amine congener, we attempted to elucidate its mechanism of action. The EC50 of berberine, β-hydrastine, canadine and canadaline, were 34.2±0.6, 72.8±0.6, 11.9±1.2 and 2.4±0.8 μg/ml, respectively. Timolol effectively antagonized the effect of canadine (EC50=19.7±3.0 μg/ml) and canadaline (EC50=17.1±1.2 μg/ml) but not that of berberine and β-hydrastine, while xanthine amine congener antagonized the effect of β-hydrastine (EC50=149.9±35.3 μg/ml) and canadaline (EC50=26.1±3.0 μg/ml) but not that of berberine and canadine. Besides, the hydrastis extract, at concentrations between 0.01 and 0.1 μg/ml, potentiated the relaxant effect of isoprenaline on carbachol-precontracted isolated guinea pig trachea. These data, which are insufficient to draw definite mechanistic conclusions, indicate that the aforementioned alkaloids may act by interacting with adrenergic and adenosinic receptors." \\ | "Hydrastis or goldenseal, one of the most popular medicinal herbs in the U.S.A., is used in mild pathological conditions like cold and flu, based on the pharmacological properties of its active components, [[https://en.wikipedia.org/wiki/Berberine|berberine]] (anticholinergic, antisecretory, and antimicrobial) and β-hydrastine (astringent). We previously reported the relaxant effect of a total ethanolic extract of hydrastis on carbachol precontracted isolated guinea pig trachea, and with the present study, using the same experimental model, we aimed at evaluating the contribution of its major alkaloids, berberine, β-hydrastine, canadine and canadaline to the total effect. Furthermore, using specific pharmacological tools, like timolol and xanthine amine congener, we attempted to elucidate its mechanism of action. The EC50 of berberine, β-hydrastine, canadine and canadaline, were 34.2±0.6, 72.8±0.6, 11.9±1.2 and 2.4±0.8 μg/ml, respectively. Timolol effectively antagonized the effect of canadine (EC50=19.7±3.0 μg/ml) and canadaline (EC50=17.1±1.2 μg/ml) but not that of berberine and β-hydrastine, while xanthine amine congener antagonized the effect of β-hydrastine (EC50=149.9±35.3 μg/ml) and canadaline (EC50=26.1±3.0 μg/ml) but not that of berberine and canadine. Besides, the hydrastis extract, at concentrations between 0.01 and 0.1 μg/ml, potentiated the relaxant effect of isoprenaline on carbachol-precontracted isolated guinea pig trachea. These data, which are insufficient to draw definite mechanistic conclusions, indicate that the aforementioned alkaloids may act by interacting with adrenergic and adenosinic receptors." \\ |
| [Relaxant effects of Hydrastis canadensis L. and its major alkaloids on guinea pig isolated trachea., Abdel‐Haq, H., Cometa, M.F., Palmery, M., Leone, M.G., Silvestrini, B., Saso, L., Pharmacology & toxicology, 87(5), 2000, 218-222] | [Relaxant effects of Hydrastis canadensis L. and its major alkaloids on guinea pig isolated trachea., Abdel‐Haq, H., Cometa, M.F., Palmery, M., Leone, M.G., Silvestrini, B., Saso, L., Pharmacology & toxicology, 87(5), 2000, 218-222] |
