基于海马-HPA轴通路研究热敏灸干预肠易激综合征的效应机制

Irritable bowel syndrome (IBS)is a kind of functional gastrointestinal disorder that is manifest in abdominal pain and abdominal discomfort along with defecation abnormality, characterised by problems of recurring and difficulty to cure. Its pathogenesisis is closely related toHPA axis anomaliesinduced by the hippocampus of GR and NMDAR. One of the advantages of acupuncture is regulating the whole for the treatment of IBS, The thermal state acupoints are the best selection in moxibustion. By moxibusting the thermal state acupoints, itcan easily excited the qi transmission in the meridian and lead qi straightly to the disfunctional position,so as to improve the clinical efficacy. Based on clinical scientific research , combined with TTM technology, we used heat-sensitive moxibustion method in treating rats with irritable bowel syndrome on "mingmen" point which is a highly heat-sensitive area as interventions in this study. At the same time,by using iGR and NMDAR in Hippocampus as the entry point ,IBS rats which were induced by chronic restraint stress as the subjects and GR antagonist RU-38 486 and NR agonist NMDA as control ,we observed the intervention effect on the gastrointestinal motility and morphology of IBS rat by heat-sensitive moxibustion and through the mechanistic investigation of NMDAR and the HPA axis regulated by GC/ iGR to provide some experimental evidence for the clinical application of heat-sensitive moxibustion in treating IBS.

肠易激综合征（IBS）是以腹痛、腹部不适伴排便异常为主要特征的功能性胃肠疾病，具有反复发作、较难治愈等特点。其发病机制与海马GR、NMDAR致HPA轴异常有密切关系，针灸治疗IBS具有整体调节等优势，而热敏穴作为灸疗最佳选穴，艾灸热敏穴极易激发经气感传，气至病所，提高临床疗效。本研究以临床科研为依据，以红外成像为热敏穴检测技术，以热敏灸IBS大鼠"命门" 穴为干预措施，以海马内iGR及NMDAR为研究的切入点，以慢性束缚应激所致IBS大鼠为观察对象，以GR拮抗剂RU-38486及NR兴奋剂NMDA为对照，运用ELISA、Real time-PCR、Western blot、免疫组化等多种技术手段，观察热敏灸对IBS大鼠胃肠运动功能及形态学的干预效应及通过NMDAR和GC/iGR调控HPA轴的机制研究，为热敏灸治疗IBS的临床应用提供部分实验依据。

肠易激综合征（IBS）是以腹痛、腹部不适伴排便异常为主要特征的功能性胃肠疾病，具有反复发作、较难治愈等特点，其发病机制与海马GR、NMDAR致HPA轴异常有密切关系。热敏灸治疗IBS临床疗效确切，热敏灸治疗IBS是否与调控NMDAR和iGR等表达有关，继而调控HPA轴途径以达到治疗IBS作用。. 第一部分实验将56只SD雄性大鼠按随机数字表随机分为空白组（8只）、模型组（8只）、艾灸组（32只），米非司酮组（RU-486组，8只），空白组正常饲养，模型组、RU-486组与艾灸组采用慢性不可预见性刺激法建立IBS模型，造模21天。造模结束后，艾灸组灸“命门”穴，每日1次，每次40min，共14天，每隔5 min检测大鼠尾温并记录，根据大鼠尾温变化分热敏灸组和非热敏灸组, 两组各随机抽取8只；RU-486组RU-486灌胃处理，空白组与艾灸组灌服同等换算体积0.9%NaCl溶液14天。实验结束后检测各组数据，发现热敏灸通过增加iGR表达，恢复了对IBS大鼠HPA轴负反馈调节，抑制HPA轴过度兴奋，达到对IBS大鼠胃肠运动功能的干预调控作用。. 第二部分实验将64只SD雄性大鼠随机分为空白组（8只）、模型组（8只）、艾灸组（32只）、假手术组（8只）、NNMDA组（8只），造模方法同上，假手术组、艾灸组和NMDA组于造模第15 d进行脑立体定位，海马处植入套管。热敏灸组和非热敏灸组分组同上。造模完成当天、第8、15 d，NMDA组海马微量注射NMDA（5μg/μL），假手术组、艾灸组注射等量生理盐水。观察各组大鼠行为学及内脏敏感性变化。治疗结束后腹主动脉取血，冰上无菌剥离大鼠脑部下丘脑、海马区进行检测。结果显示热敏灸组iGR表达明显升高，NR1、NR2A、NR2B表达明显降低，表明了热敏灸通过抑制NR表达，促进iGR释放，下丘脑CRH分泌减少，从而调控HPA通路的调控机制。. 本研究以海马内iGR及NMDAR为研究的切入点，以慢性束缚应激所致IBS大鼠为观察对象，以GR拮抗剂RU-38486及NR兴奋剂NMDA为对照，运用ELISA、Real time-PCR、Western blot等多种技术手段，观察热敏灸对IBS大鼠胃肠运动功能及形态学的干预效应及通过NMDAR和GC/iGR调控HPA轴的机制研究，为热敏灸治疗IBS的临床应用提供了部分实验依据.