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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Calcium, Calcium Channel Blockers, Erythrina, Female, GABA Antagonists, Guinea Pigs, Ileum, Male, Muscarinic Antagonists, Muscle Contraction, Muscle, Smooth, Plant Extracts, Plant Leaves, Sodium Channel Blockers.
user
Does evidence of the mechanism of action of Erythrina velutina Willd ( Fabaceae ) leave aqueous extract? Context: Erythrina velutina is traditionally used for sleepiness, convulsions and nervous system excitation in Brazil. Although central effects have been reported for Erythrina velutina, little is known about its mechanism of action. To investigate the pharmacological evidences of mechanism of action of Erythrina velutina leaves aqueous extract (AE). Terminal segments of the guinea-pig ileum (n=5-8) were mounted in an organ bath and isotonic contractions were recorded. Phytochemical screening was carried out on AE. AE (0.025-2.50 mg/ml) produced contractile response in the guinea-pig ileum, yielding typical concentration-response curves (EC50=0.63 mg/ml). Electrically evoked contractions were significantly increased in the presence of AE. AE-elicited contractions were significantly reduced by bicuculline, tetrodotoxin, atropine, verapamil or incubation in low calcium-high potassium solution. Atropine along with verapamil abolished AE contractile response. Alkaloids, catechins, steroids, flavonols, flavononols, flavonoids, phenols, saponins, tannins, triterpenoids, and xanthones were detected in AE.
assistant
AE contains important constituents for pharmacological activities. AE-induced contractions seem to involve GABAA receptor activation, acetylcholine release, muscarinic receptor activation, augmentation of Ca2+ entry through L-type calcium channels, and calcium release from the intracellular stores. These findings provide further support for Erythrina velutina traditional uses. Final Decision: yes