Ability of mosapride to bind to 5-HT4 receptor in the human stomach

Ability of mosapride, a gastrokinetic agent, to bind to 5-HT4 receptor was examined in the stomach of human and guinea pig by in vitro receptor autora diography. [(125)]SB207710 binding sites were detected in the muscle layer including the myenteric plexus of the stomach from both humans and guinea p igs, although the binding was observed more clearly and densely in the stom ach of guinea pigs than humans. Mosapride as well as SB204070 inhibited the binding of [I-125]SB207710. Thus. mosapride possesses the ability to bind to 5-HT4 receptors of human stomach and may modulate the motility, as in th e case of guinea pig stomach.