Meissner A J, Bowes K L, Zwick R, Daniel E E
Gut. 1976 Dec;17(12):925-32. doi: 10.1136/gut.17.12.925.
The effect of motilin on lower oesophageal sphincter (LES) pressure has been studied in unanesthetised specially trained dogs using an infusion manometric technique. Motilin produced significant rises in resting pressure and contractions of the LES after doses ranging from 0-009 mug/kg to 0-05 mug/kg. Doses greater than 0-05 mug/kg resulted in repetitive high amplitude contractions. Atropine 30 mug/kg completely abolished the effect of the lower doses of motilin. Higher doses of motilin in atropinised dogs still caused a small rise in baseline pressure and contractile activity still appeared. Hexamethonium 2 mg/kg resulted in both a diminished rise in LES pressure and the disappearance of contractions after motilin. Hexamethonium and atropine together completely abolished the LES response to motilin. We conclude that motilin increases LES pressure by acting on preganglionic cholinergic neurones to release acetylcholine which excites other cholinergic neurones supplying the circular muscle of the LES.
采用灌注测压技术，在未经麻醉的受过特殊训练的犬身上研究了胃动素对食管下括约肌（LES）压力的影响。胃动素剂量在0.009微克/千克至0.05微克/千克范围内时，可使LES的静息压力和收缩显著升高。剂量大于0.05微克/千克会导致重复性高振幅收缩。30微克/千克的阿托品可完全消除较低剂量胃动素的作用。在已用阿托品处理的犬中，较高剂量的胃动素仍会使基线压力略有升高，且仍会出现收缩活动。2毫克/千克的六甲铵可使胃动素作用后LES压力升高幅度减小且收缩消失。六甲铵和阿托品共同作用可完全消除LES对胃动素的反应。我们得出结论，胃动素通过作用于节前胆碱能神经元释放乙酰胆碱来增加LES压力，乙酰胆碱会兴奋供应LES环形肌的其他胆碱能神经元。
