胃泌素和胃动素对人离体食管下括约肌张力的调节机制

Regulation of gastrin and motilin on the tension of human lower esophageal sphincter in vitro

目的探讨胃泌素和胃动素对人类食管下括约肌的套索纤维和钩状纤维的作用规律。方法制备人食管下括约肌的套索纤维、钩状纤维以及食管体部和胃底环行肌的肌条,运用离体组织张力测量技术,得出各肌条对胃泌素和胃动素的剂量-反应曲线和最大收缩效应值(Emax)。结果各类肌条对胃泌素和胃动素产生了规律及强度明显不同的浓度-依赖性收缩。套索纤维对胃泌素的Emax值[(4.91±0.95)mN/mm2]显著高于钩状纤维[(0.72±0.14)mN/mm2]。套索纤维和钩状纤维对胃动素均产生较强的收缩反应[(3.61±0.65)mN/mm2和(2.64±0.33)mN/mm2]。结论人类食管下括约肌的套索纤维和钩状纤维对胃泌素和胃动素具有明显不同的反应特性。

Objective To explore the regulatory mechanism of gastrin and motilin on sling fibers and clasp fibers of human lower esophageal sphincter. Methods Muscle strips of the sling and clasp fibers from human lower esophageal sphincter and the circular layers of the esophagus and gastric fundus were obtained from patients with subtotal esophagectomy. Through the isolated tissue tension detection technique and pharmacological method, the concentration-response curves of the strips responding to gastrin and motilin were constructed, from which Emax s were derived. Results All strips contracted to gastrin and motilin with different rules and different intensity in a concentration-dependent fashion. Sling fibers＇ Emax value （4.91 ± 0.95 mN/mm/^2 ） to gastrin was significantly higher than clasp fibers＇ （0.72 ± 0.14 mN/mm/^2）. Otherwise, in response to motilin, both sling fibers and clasp fibers contracted to motilin intensively （3.61± 0.65 mN/mm/^2 and 2.64 ± 0.33 mN/mm/^2 ）. Conclusions The sling fibers and clasp fibers have different responses to gastrin and motilin.