Lippia alnifolia essential oil induces relaxation on Guinea-pig trachea by multiple pathways.
J Ethnopharmacol
; 246: 112162, 2020 Jan 10.
Article
en En
| MEDLINE
| ID: mdl-31419501
ABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE Lippia alnifolia Mart. & Schauer, known as "alecrim-do-mato", "alecrim-de-vaqueiro" and "pedrécio", is used in folk medicine as antiseptic and to treat diseases that affect respiratory system, like bronchitis and asthma. AIM OF THE STUDY The aim of this work was to investigate the spasmolytic activity and relaxant mechanism of the Lippia alnifolia essential oil (EOLA) on isolated guinea-pig trachea and to correlate with its use in folk medicine. MATERIALS AND METHODS:
Leaves from L. alnifolia were collected in Pico das Almas, Chapada Diamantina, situated in the city of Rio de Contas, Bahia, Brazil. EOLA was extracted by hydrodistillation, analyzed by GC/FID and GC/MS and the volatile constituents were identified. Spasmolytic activity was assayed in isolated guinea-pig trachea pre-contracted with carbachol 1⯵M or histamine 10⯵M. Relaxant mechanism of EOLA was determined comparing concentration-response curves in the presence or absence of different blockers.RESULTS:
Chemical analysis revealed the presence of carvone (60⯱â¯0.8%) as major constituent. EOLA (1-243⯵g/mL) relaxed isolated guinea-pig trachea pre-contracted with carbachol 1⯵M [EC50â¯=â¯53.36 (44.75-63.51) µg/mL] or histamine 10⯵M [EC50â¯=â¯5.42 (4.42-6.65) µg/mL]. The pre-incubation of 4-aminopyridine in histamine-induced contractions did not alter significantly the relaxant effect of EOLA. However, the presence of cesium chloride, glibenclamide, tetraethylammonium, propranolol, indomethacin, dexamethasone, hexamethonium, atropine, L-NAME, methylene blue or ODQ reduced EOLA relaxant effect. EOLA 18⯵g/mL pre-incubation in calcium-free medium reduced histamine-evoked contractions, but did not alter histamine contractions in the presence of nifedipine.CONCLUSIONS:
Lippia alnifolia essential oil has spasmolytic activity on isolated guinea-pig trachea and its mechanism of action possibly involves the activation of multiple signal transduction pathways, which culminate in potassium channels activation and cytosolic calcium reduction.Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Parasimpatolíticos
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Tráquea
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Aceites Volátiles
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Lippia
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Año:
2020
Tipo del documento:
Article