[Effect of motilin on contractile activity of isolated smooth muscle of stomach].
The present study was conducted to investigate the contractile effect of motilin on isolated smooth muscle cells of rat stomach. The results were as follows: (1) Motilin elicited contraction of gastric smooth muscle cells in a dose-dependent manner from 10(-11) to 10(-10) mol. (2) At concentration of 10(-10) mol, the contractile response of antral smooth muscle cells exceeded that of the body and pyrous muscle cells. (3) Anti-motilin serum could completely eliminate the stimulatory effect of motilin, which was not affected by atropine, TTX, cimetidine or loxiglumide. (4) TMB-8, an inhibitor of intracellular Ca2+ release, could also suppress completely the motilin effect. The above results suggested that the motilin effect on isolated gastric smooth muscle cells is a direct one, being mediated by highly specific motilin receptors in connection with the event of intracellular release of Ca2+.
Zhou
L
L
Department of Physiology, CAMS, Beijing.
Wang
X
X
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology; D005707:Gallic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D009037:Motilin / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000166:cytology / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013270:Stomach / Q000502:physiology
D002121:Calcium Channel Blockers; D009037:Motilin; C006014:8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate; D005707:Gallic Acid; D002118:Calcium