大鼠早期生活应激对成年后功能性慢性内脏痛及下丘脑室旁核内CRH R1表达的影响  

Effect of early-life stress on chronic functional visceral pain and CRH R1 expression in the paraventricular nucleus in adult rats

作　　者：赵小平[1] 喻乐[1] 陈自洋 花嵘[2] 张咏梅[1] 

机构地区：[1]徐州医学院江苏省麻醉学重点实验室,江苏省徐州市221004 [2]中国人民解放军第九七医院急诊科,江苏省徐州市221004

出　　处：《世界华人消化杂志》2013年第31期3344-3355,共12页World Chinese Journal of Digestology

基　　金：国家自然科学基金资助项目;No.81171041;江苏省自然科学基金资助项目;No.BK2011197;江苏省高校自然科学研究重大项目;No.13KJA320001;江苏省2012年度普通高校研究生科研创新计划基金资助项目;No.XYYC-1214~~

摘　　要：目的:探讨建立功能性慢性内脏痛的不同造模方式及造成的功能性慢性内脏痛的性别差异;观察功能性慢性内脏痛大鼠下丘脑室旁核(paraventricular nucleus,PVN)内促肾上腺皮质激素释放激素受体1(corticotropin releasing hormone receptor 1,CRH R1)表达变化,进而认识下丘脑PVN在功能性慢性内脏痛发生中的作用及机制,为临床防治功能性慢性内脏痛提供理论依据.方法:将新生期S D大鼠随机分成雌雄对照组、雌雄母婴分离(neonatal maternal separation,NMS)组、雌雄直结肠扩张(colorectal distension,CRD)组,每组10只,成年后进行直结肠内扩张后,采用腹壁撤离反射(abdominal withdrawal reflex,AWR)和电生理学方法评价其内脏痛觉敏感性;采用HE染色检测结肠组织形态学变化;采用Western blot、免疫荧光染色方法检测PVN内CRH R1及c-fos的表达变化.将正常成年大鼠随机分为正常对照组、生理盐水组和利多卡因组,每组6只,通过PVN内微量注射利多卡因观察PVN在正常大鼠内脏痛觉调节中的作用.结果:(1)大鼠新生期经历母婴分离、直结肠扩张,成年后AWR评分、腹外斜肌放电幅度增高,痛阈值下降,结肠组织均未见明显病理改变,其中NMS组在20 mmHg直结肠扩张时AW R评分和腹外斜肌放电幅度均比C R D组高(P<0.05,P<0.05);(2)各组大鼠雌雄AWR评分、痛阈值和腹外斜肌放电幅度差别不一致,但大部分是没有性别差异的;(3)与正常对照组、生理盐水组相比,PVN内微量注射1%利多卡因后10、20、30 min在60 mmHg直结肠扩张时腹外斜肌放电是明显下降的(P<0.05).(4)N M S、C R D组与对照组比较,P V N内c-fos、CRH R1的表达增加(P<0.05,P<0.05).结论:早期生活应激会导致成年后功能性慢性内脏痛的发生,NMS导致的触诱发痛(allodynia)更明显,但没有性别差异.PVN及其内的CRH R1参与大鼠早期生活应激引起的功能性慢性内脏痛的形成和维持.AIM： To assess the effect of early-life stress on chronic functional visceral pain and expression of corticotropin releasing hormone receptor 1 （CRH R1） in the hypothalamic paraventricular nucleus （PVN） of rats with chronic functional visceral pain to provide a theoretical basis for the prevention and treatment of abdominal pain- related functional gastrointestinal disorders. METHODS： Neonatal rats were randomly di- vided into six groups （n = 10）, including a male control group, a female control group, a male separation group, a female separation group, a male distension group and a female distension group. HE staining was used to detect histologic changes in the colon tissue. Western blot and immunofluorescence were used to detect the changes in CRH R1 expression in the PVN. Brain tissue sections were immunostained for c-fos as a marker for activation of the PVN. Furthermore, normal male adult rats were randomly divided into three groups （normal control, saline and li- docaine, n = 6 for each group） to observe the role of PVN in the regulation of chronic functional visceral pain in normal rats by intra-PVN ad- ministration of lidocaine （1%, 0.3 μL）. RESULTS： Neonatal maternal separation （N MS） or colorectal distension （CRD） resulted in chron- ic visceral hypersensitivity without pathologi- cal changes in the colon tissue. There was no gender difference in the above change. Electrical discharge of the abdominal external oblique muscle in rats 10, 20, and 30 min after intra-PVN microinjection of 1% lidocaine was decreased significantly under the stimulation of CRD at 60 mmHg compared with normal controls and sa- line rats. The expression of CRH R1 and c-los in the PVN of NMS and CRD rats increased com- pared with control rats. CONCLUSION： Early-life stress can lead to chronic functional visceral pain in rats in adult- hood. Allodynia caused by NMS is more obvi- ous than that by CRD. The PVN and CRH R1 may be involved in the pathogenesis of chronic functional visceral pain cause

关 键 词：早期生活应激 功能性慢性内脏痛 雌雄母婴分离 雌雄直结肠扩张 下丘脑室旁核 促肾上腺皮质激素释放激素受体1 

分 类 号：R363[医药卫生—病理学]