中文摘要：

目的应用人食管下括约肌的套索纤维和钩状纤维，观察胃动素受体（MTLR）在套索纤维和钩状纤维的表达和胃动素对套索纤维和钩状纤维的收缩作用。方法采用逆转录一聚合酶链反应（RT—PCR）技术和Western blot技术观察人食管下括约肌套索纤维和钩状纤维MTLR的表达，应用倒置显微镜观察胃动素引起的套索纤维和钩状纤维长度的变化。结果胃动素受体在套索纤维和钩状纤维均有表达，套索纤维表达高于钩状纤维；胃动素对套索纤维和钩状纤维均存在收缩作用，胃动素对套索纤维的收缩作用强于钩状纤维。结论胃动素通过人食管下括约肌套索纤维和钩状纤维的胃动素受体，激发食管下括约肌的收缩，其对套索纤维的收缩作用大于钩状纤维。

英文摘要：

Objective The aim of the study was to investigate the expression of motilin receptor in sling and clasp fibers of the human lower esophageal sphincter and different contraction, responses of the two muscles to motilin. Methods Reverse transcription-polymerase chain reaction （RT-PCR） and West- ern blotting were used to detect MTLR in the human sling fibers and clasp fibers. Inverted microscope was used to measure length changes of the sling and clasp fibers which were induced by motilin. Results MTLR were expressed both in the sling fibers and clasp fibers. Expression of MTLR in sling fibers was higher than in clasp fibers. The contraction in the sling fibers was stronger than in clasp fibers. Conclusion The contraction of the sling and clasp fibers in human esophageal sphincter is induced by motilin through MTLR. The contraction in the sling fibers is stronger than in clasp fibers.