['Several Asian plants are known for their anti-diabetic properties and produce alkaloids and flavonoids that may stimulate insulin secretion.', "Using Vietnamese plants (Nelumbo nucifera, Gynostemma pentaphyllum, Smilax glabra, and Stemona tuberosa), we extracted two alkaloids (neotuberostemonine, nuciferine) and four flavonoids (astilbin, engeletin, smitilbin, and 3,5,3'-trihydroxy-7,4'-dimethoxyflavone), and studied their insulin stimulatory effects.", 'Nuciferine, extracted from Nelumbo nucifera, stimulated both phases of insulin secretion in isolated islets, whereas the other compounds had no effect. The effect of nuciferine was totally abolished by diazoxide and nimodipine, and diminished by protein kinase A and protein kinase C inhibition. Nuciferine and potassium had additive effects on insulin secretion. Nuciferine also stimulated insulin secretion in INS-1E cells at both 3.3 and 16.7 mM glucose concentrations. Compared with glibenclamide, nuciferine had a stronger effect on insulin secretion and less beta-cell toxicity. However, nuciferine did not compete with glibenclamide for binding to the sulfonylurea receptor.'] Does nuciferine stimulate insulin secretion from beta cells-an in vitro comparison with glibenclamide?