title: [Effects of trimebutine maleate (TM-906) on the spontaneous contraction of the isolated guinea pig stomach].
abstract: Effects of trimebutine maleate (TM-906) on the spontaneous contraction were investigated in the isolated circular smooth muscle of the antrum region of the guinea pig stomach. TM-906 dose-dependently reduced the amplitude of the regular spontaneous contraction without any marked change in its frequency and basal tension. This effect of TM-906 was also observed in the presence of phentolamine, propranolol, atropine, and tetrodotoxin. However, the inhibitory effect of TM-906 was overcome by increasing the extracellular concentration of CaCl2. On the other hand, in preparations which exhibited irregular spontaneous contraction, TM-906 regularized it, and spontaneous contraction with regular frequency and amplitude was elicited. In addition, this regularizing effect of TM-906 was also observed in the presence of atropine and tetrodotoxin. It was concluded that TM-906 has dual effects on the spontaneous contraction, reducing the amplitude of regular contraction and regularizing the irregular contraction. These effects of TM-906 may be attributed to the direct action on the smooth muscle.
mesh_terms: D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001565:Benzoates / Q000494:pharmacology*; D002118:Calcium / Q000494:pharmacology; D004110:Diltiazem / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006168:Guinea Pigs; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D010208:Papaverine / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011706:Pyloric Antrum / Q000187:drug effects; D013779:Tetrodotoxin / Q000494:pharmacology; D014287:Trimebutine / Q000494:pharmacology*
chemical_list: D001565:Benzoates; D013779:Tetrodotoxin; D001285:Atropine; D011433:Propranolol; D010208:Papaverine; D004110:Diltiazem; D014287:Trimebutine; D002118:Calcium; D010646:Phentolamine