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Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
Published on: August 18, 2014
[Norstephalagine and atherospermidine: two smooth muscle relaxant aporphines from Artabotrys maingayi]
D Cortes1, M Y Torrero, M Pilar D'Ocon
1Laboratoire de Pharmacognosie, Faculté de Médecine et Pharmacie, Université de Rouen, Saint Etienne du Rouvray, France.
Abstract:
Nine isoquinoline alkaloids have been isolated from the bark of Artabotrys maingayi: four noraporphines (norstephalagine, 3-hydroxynornuciferine, anonaine, and nornuciferine), one 7-hydroxyaporphine (ushinsunine), three oxoaporphines (atherospermidine, liriodenine, and lysicamine), and one protoberberine (discretamine). The effects of the main alkaloids, norstephalagine and atherospermidine, have been studied on the Ca-dependent contractile activity of smooth muscle (uterus). Both norstephalagine and atherospermidine show relaxing activity on rat uterine contractions induced by KCl or rhythmic contractions induced by oxytocin in the presence of Ca, but only atherospermidine can relax oxytocin- or vanadate-induced contractions in a Ca-free medium.
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