title: Antiulcerogenic activity of a crude hydroalcoholic extract and coumarin isolated from Mikania laevigata Schultz Bip.
abstract: The leaves of Mikania (Asteraceae) species are used in folk medicine as antispasmodic, antiulcerogenic and antirheumatic agents. Phytochemical screening of the crude hydroalcoholic 70% extract (CHE) of Mikania laevigata Shultz Bip. revealed coumarins, terpenes and organic acids. Antiulcerogenic activity of CHE was evaluated, employing different experimental models in rats, to discern the pharmacological mechanism of action. Both the antisecretory and the cytoprotection hypothesis were evaluated. The crude hydroalcoholic extract (1000 mg/kg body wt., vo) decreased the ulcerative lesion index produced by indomethacin, ethanol, stress and reserpine in rats by 85%, 93%, 82% and 50%, respectively. In the pyloric ligation model, a decrease of hydrogenionic concentration (53%) was observed, suggesting that the pharmacological mechanism has a relationship to antisecretory activity. The antisecretory mechanisms of CHE and the coumarin isolated from M. laevigata were confirmed by acid hypersecretion induced by histamine, pentagastrin and bethanechol. Duodenal administration of CHE (1000 mg/kg body wt.) and coumarin (100 mg/kg body wt.) inhibited only the gastric acid secretion produced by bethanecol. These results suggest that both CHE and coumarin may influence the secretion control mediated by the parasympathetic system.
authors.affiliation: Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas, Universidade Estadual de Campinas, Campinas, São Paulo, Brasil.
authors.forename: A E
authors.initials: AE
authors.lastname: Bighetti
authors.forename: M A
authors.initials: MA
authors.lastname: Antônio
authors.forename: L K
authors.initials: LK
authors.lastname: Kohn
authors.forename: V L G
authors.initials: VL
authors.lastname: Rehder
authors.forename: M A
authors.initials: MA
authors.lastname: Foglio
authors.forename: A
authors.initials: A
authors.lastname: Possenti
authors.forename: L
authors.initials: L
authors.lastname: Vilela
authors.forename: J E
authors.initials: JE
authors.lastname: Carvalho
mesh_terms: D000818:Animals; D000897:Anti-Ulcer Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D000925:Anticoagulants / Q000008:administration & dosage / Q000627:therapeutic use; D003374:Coumarins / Q000008:administration & dosage / Q000627:therapeutic use; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004381:Duodenal Ulcer / Q000139:chemically induced / Q000517:prevention & control*; D000431:Ethanol; D007213:Indomethacin; D008297:Male; D035742:Mikania; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000627:therapeutic use*; D018515:Plant Leaves; D051381:Rats; D017208:Rats, Wistar; D012110:Reserpine; D013312:Stress, Physiological
chemical_list: D000897:Anti-Ulcer Agents; D000925:Anticoagulants; D003374:Coumarins; D010936:Plant Extracts; D000431:Ethanol; D012110:Reserpine; C030123:coumarin; D007213:Indomethacin