Effects of genistein, an isoflavone isolated from Genista tridentata, on isolated guinea-pig ileum and guinea-pig ileal myenteric plexus.
The inhibitory action of the major constituent of Genista tridentata L. (Papilionaceae), 4',5,7-trihydroxyisoflavone (genistein), on contractions induced by agonists and electrical field stimulation of smooth muscle was analysed. Genistein inhibited twitches evoked by electrical-stimulation of strips of guinea-pig ileum with an IC50 value of 34 microM. Genistein (34 microM) inhibited contractions of the guinea-pig ileum by several agonists in a non-selective, antispasmodic action and had no effect on inhibition of 3H-ACh release from ileal myenteric plexus. Genistein (34 microM) produces an increase in cAMP levels of guinea-pig ileum which resulted in a smooth muscle relaxation which leads us to think that there must be a blockade of its phosphodiesterase.
Herrera
M D
MD
Departamento de Farmacia y Tecnología Farmaceútica, Facultad de Farmacia, Universidad de Sevilla, Spain.
Marhuenda
E
E
Gibson
A
A
D000818:Animals; D046508:Culture Techniques; D019833:Genistein; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects; D007529:Isoflavones / Q000302:isolation & purification / Q000494:pharmacology*; D008297:Male; D009197:Myenteric Plexus / Q000187:drug effects; D010276:Parasympatholytics / Q000302:isolation & purification / Q000494:pharmacology*; D010944:Plants / Q000737:chemistry*
D007529:Isoflavones; D010276:Parasympatholytics; D019833:Genistein