Phymatodes scolopendria (Burm.) Ching (Polypodiaceae) is widely used in the Eastern coast of Madagascar to treat respiratory disorders. Bioassay-guided fractionation using guinea pig trachea pre-contracted with histamine to monitor the activity led to the isolation of 1,2-benzopyrone (coumarin) as the main active constituent. Effectively, it induced a concentration-dependent relaxation of the histamine with a median effective concentration (EC50) of 35.03g/ml, or carbachol (EC50 = 33.41g/ml) pre-contracted guinea pig trachea, and also provoked 100% relaxation at 72.10g/ml. It was less active either on KCl pre-contracted trachea (EC50 = 130.78g/ml) or endothelium denuded trachea (153.4±22g/ml). It inhibited, in a non-competitive manner, the histamine and the external calcium spasm effect on the isolated trachea but it did not significantly modify the broncho-constrictive activity of KCl. When combined with theophylline, coumarin produced a significant additive relaxing effect on pre-contracted trachea. Furthermore, its bronchodilator effect was not blocked by propranolol. In vivo, pre-treated guinea pig with coumarin showed significant resistance to histamine inhalation, with an adequate dose protecting 50% of the tested animals (AD50) of 75 mg/kg. These results indicate that the bronchodilator effect of coumarin is partly due to the endothelium-dependent tracheal relaxation, and may be mediated through a non-specific tracheal relaxation.

Broncodilatatory activity of Phytomatodes scolopendria (Burn.) Ching and its bioactive constituents / D., Ramanitrahasimbola; D. A., Rakotondramanana; P., Rasoanaivo; A., Randriantsoa; S, Ratsimamanga; G., Palazzino; C., Galeffi; Nicoletti, Marcello. - In: JOURNAL OF ETHNOPHARMACOLOGY. - ISSN 0378-8741. - 102:(2005), pp. 400-407. [10.1016/j.jep.2005.06.037]

Broncodilatatory activity of Phytomatodes scolopendria (Burn.) Ching and its bioactive constituents

NICOLETTI, Marcello
2005

Abstract

Phymatodes scolopendria (Burm.) Ching (Polypodiaceae) is widely used in the Eastern coast of Madagascar to treat respiratory disorders. Bioassay-guided fractionation using guinea pig trachea pre-contracted with histamine to monitor the activity led to the isolation of 1,2-benzopyrone (coumarin) as the main active constituent. Effectively, it induced a concentration-dependent relaxation of the histamine with a median effective concentration (EC50) of 35.03g/ml, or carbachol (EC50 = 33.41g/ml) pre-contracted guinea pig trachea, and also provoked 100% relaxation at 72.10g/ml. It was less active either on KCl pre-contracted trachea (EC50 = 130.78g/ml) or endothelium denuded trachea (153.4±22g/ml). It inhibited, in a non-competitive manner, the histamine and the external calcium spasm effect on the isolated trachea but it did not significantly modify the broncho-constrictive activity of KCl. When combined with theophylline, coumarin produced a significant additive relaxing effect on pre-contracted trachea. Furthermore, its bronchodilator effect was not blocked by propranolol. In vivo, pre-treated guinea pig with coumarin showed significant resistance to histamine inhalation, with an adequate dose protecting 50% of the tested animals (AD50) of 75 mg/kg. These results indicate that the bronchodilator effect of coumarin is partly due to the endothelium-dependent tracheal relaxation, and may be mediated through a non-specific tracheal relaxation.
2005
01 Pubblicazione su rivista::01a Articolo in rivista
Broncodilatatory activity of Phytomatodes scolopendria (Burn.) Ching and its bioactive constituents / D., Ramanitrahasimbola; D. A., Rakotondramanana; P., Rasoanaivo; A., Randriantsoa; S, Ratsimamanga; G., Palazzino; C., Galeffi; Nicoletti, Marcello. - In: JOURNAL OF ETHNOPHARMACOLOGY. - ISSN 0378-8741. - 102:(2005), pp. 400-407. [10.1016/j.jep.2005.06.037]
File allegati a questo prodotto
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/239932
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? 6
  • Scopus 22
  • ???jsp.display-item.citation.isi??? 21
social impact