Cuomo Rosario, Vandaele Pieter, Coulie Bernard, Peeters Theo, Depoortere Inge, Janssens Jozef, Tack Jan
Department of Internal Medicine, Division of Gastroenterology, University Hospital Gasthuisberg, University of Leuven, Leuven, Belgium.
Am J Gastroenterol. 2006 Apr;101(4):804-11. doi: 10.1111/j.1572-0241.2005.00339.x.
Motilin agonists are strong gastroprokinetics, but their impact on symptoms in delayed gastric emptying has been disappointing. It has been speculated that it is due to the contractile effect of motilin agonists on the proximal stomach, but the pathway involved and the symptomatic consequences have been incompletely elucidated.
To study whether motilin enhances proximal stomach tone and enhances meal-induced satiety and to evaluate whether this effect involves a cholinergic pathway.
A gastric barostat was used to study, in healthy subjects, the effect of motilin (300 ng/kg/30 min i.v.) or saline on fasting gastric fundus tone and on post-prandial relaxation. To evaluate the involvement of a cholinergic pathway, atropine (12 microg/kg/h) was administered intravenously simultaneously with or before and during motilin infusion in the fasting state. Finally, a satiety drinking test was performed in 21 subjects twice after pretreatment with placebo or motilin and with placebo or atropine.
Administration of motilin caused a significant increase of fasting fundus tone expressed as decrease of the mean balloon volume (324 +/- 60 mL vs 213 +/- 62 mL, p < 0.05). Simultaneous administration of atropine and motilin did not generate a significant volume change (192 +/- 60 mL vs 181 +/- 83 mL, NS), but pretreatment with atropine alone induced a relaxation, and when motilin was added this revealed an ongoing contraction (192 +/- 24 mL vs 136 +/- 21 mL, p < or = 0.05). Motilin infusion also inhibited gastric accommodation (p < or = 0.05 vs placebo) and increased satiety during a satiety drinking test (p < or = 0.05 vs placebo).
Administration of motilin causes a contraction of the proximal stomach in humans and increases meal-induced satiety. The effect of motilin is atropine-resistant and involves a direct muscular pathway or a non-cholinergic neural pathway.
胃动素激动剂是强效促胃肠动力药，但它们对胃排空延迟症状的影响并不理想。据推测，这是由于胃动素激动剂对胃近端的收缩作用，但所涉及的途径和症状后果尚未完全阐明。
研究胃动素是否增强胃近端张力并增强进餐诱导的饱腹感，并评估这种作用是否涉及胆碱能途径。
使用胃内压测定仪，在健康受试者中研究胃动素（300 ng/kg/30分钟静脉注射）或生理盐水对空腹胃底张力和餐后舒张的影响。为了评估胆碱能途径的参与情况，在空腹状态下，于胃动素输注期间或之前及期间，同时静脉注射阿托品（12 μg/kg/h）。最后，对21名受试者在分别用安慰剂或胃动素以及安慰剂或阿托品预处理后进行两次饱腹感饮水试验。
注射胃动素导致空腹胃底张力显著增加，表现为平均气囊体积减小（324±60 mL对213±62 mL，p<0.05）。同时注射阿托品和胃动素未产生显著的体积变化（192±60 mL对181±83 mL，无显著性差异），但单独用阿托品预处理可诱导舒张，加入胃动素后显示出持续的收缩（192±24 mL对136±21 mL，p≤0.05）。胃动素输注还抑制胃容纳（与安慰剂相比，p≤0.05），并在饱腹感饮水试验期间增加饱腹感（与安慰剂相比，p≤0.05）。
在人类中，注射胃动素会导致胃近端收缩并增加进餐诱导的饱腹感。胃动素的作用对阿托品有抗性，并涉及直接的肌肉途径或非胆碱能神经途径。
