Autor: |
Rakotondramanana DA; Pharmacy Department, Faculty of Medicine, University of Antananarivo, Antananarivo, Madagascar., Razafindrakoto ZR; Applied Pharmacognosy Laboratory, Institut Malgache de Recherches Appliquées, Antananarivo, Madagascar., Donno D; Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università degli Studi di Torino, Turin, Italy., Tombozara N; Applied Pharmacognosy Laboratory, Institut Malgache de Recherches Appliquées, Antananarivo, Madagascar., Nalimanana NR; Applied Pharmacognosy Laboratory, Institut Malgache de Recherches Appliquées, Antananarivo, Madagascar., Andrianajara C; Applied Pharmacognosy Laboratory, Institut Malgache de Recherches Appliquées, Antananarivo, Madagascar., Beccaro GL; Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università degli Studi di Torino, Turin, Italy., Ramanitrahasimbola D; Pharmacy Department, Faculty of Medicine, University of Antananarivo, Antananarivo, Madagascar.; Applied Pharmacognosy Laboratory, Institut Malgache de Recherches Appliquées, Antananarivo, Madagascar., Nicoletti M; Department of Environmental Biology, Sapienza University of Roma, Rome, Italy. |
Abstrakt: |
Androsta-1,4-dien-3,16-dione was isolated for the first time from the plant kingdom of the ethanolic extract of the Ravenala madagascariensis ' inflorescence by the bio-guided method. Its structure was elucidated by NMR and MS spectroscopic data analysis. The vascular effects of ethanol extracts, fractions and androsta-1,4-dien-3,16-dione were assessed on the phenylephrine pre-contracted isolated rat aorta. The isolated compound exerted the most potent vaso-relaxing effect (EC 50 = 109.32 ± 15.82 µM) than the ethanol extract and fractions. The pharmacological mechanism of its vaso-relaxing action was analysed on isolated rat aorta using free-endothelial vascular tissue, specific contracting reagents (CaCl 2 and KCl), antagonist (propranolol), enzyme inhibitors (L-NAME, methylene blue) and channel blocker (glibenclamide). Its vaso-relaxing activity could be due, at least partly, to the non-specific inhibition of the calcic influx. |