Analysis of motilin receptor in human gastric antrum for clinical application of motilide

1.由于吗丁内酯不允许在人体内使用，因此我们在清醒的狗体内长期植入测力传感器，研究了吗丁内斯的生物活性。因此，EM523除了在禁食状态外，还在进食状态下引起强烈的收缩。EM523引起的胃收缩是通过胃中的胆碱能神经元，包括5-HT3受体介导的。此外，还发现EM523通过非胆碱能途径的P物质神经元引起胃收缩。2.研究发现EM523通过迷走神经胆碱能M受体兴奋胰岛激素，EM574和胃动素刺激人胃窦平滑肌的收缩活动。在放射受体结合研究中，发现胃动素受体存在于人胃窦平滑肌组织中，这种特异性结合被EM574以剂量依赖的方式取代。在放射自显影研究中，发现人胃窦平滑肌层中存在胃动素的特异性结合，这些结合也被加入EM574以剂量依赖的方式抑制。由于胃动素在人胃窦的膜部分的结合很低，所以在放射自显影研究中发现，在人胃窦的平滑肌层中发现了胃动素的特异性结合，这些结合也被加入EM574以剂量依赖的方式抑制将碘标记的胃动素与人胃平滑肌匀浆制剂结合，用十二烷基硫酸钠凝胶电泳法对结合情况进行分析。检测到三条不同相对分子质量的条带，其中一条带只有一个峰，目前正在进一步提纯。

1.Since motilides are not permitted to use in human, the biological activity of motilides was studied in conscious dogs with force transducers chronicanlly implanted in the gastrointestinal tract. As a result, EM523 induced strong contractions in the fed state in addition to the fasted state. EM523-induced contractions in the stomach is mediated through cholinergic neurons including 5-HT3 receptors in the stomach. Moreover, it was also found that EM523 induced contractions in the stomach through substance P neurons without cholinergic pathways.2.It was found that EM523 stimulates pancreatic islet hormones through vagally cholinergic muscarinic receptors.EM574 and motilin stimulated contractile activity in isolated smooth muscle of human gastric antrum. EM574 also stimulated contractile activity of smooth muscle strips of human gastric antrum in a dose-dependent manner, and these contractions were TTX-resistant.In radioreceptor binding study, it was found that motilin receptors were present in the smooth muscle tissue of the human gastric antrum, and the specific binding was replaced by EM574 in a dose-dependent fashion.In the study of autoradiography, it was found that specific bindings of motilin were found in the smooth muscle layr of the human gastric antrum, and these bindings were also inhibited by addition of EM574 in a dose-dependent manner.Since the binding of motilin in the membrane fraction of the human stomach was very low, iodinated motilin was bound to the homogenate preparation of smooth muscle in the human stomach, and the bound was analyzed by means of a SDS gel electrophoresis. The three different bands in molecular weight were detected, and a single peak could be obtained from one of the bands, and now further be purifying.