下丘脑弓状核微量注射Orexin-A对大鼠胃传入信息和胃运动的影响  

The Impact of Stomach Information and Gastric Motility in Microinjection of Orexin-A into the Rat Hypothalamic Arcuate Nucleus

作　　者：段秋霞 杨丹丹[1] 彭晓燕 郭菲菲[1] 徐珞[1] 

机构地区：[1]青岛大学医学院病理生理学教研室,山东青岛266021 [2]青岛市第三人民医院,山东青岛266021

出　　处：《现代生物医学进展》2017年第29期5628-5632,共5页Progress in Modern Biomedicine

基　　金：国家自然科学基金项目(81470815;81270460;81500414);山东省优秀中青年科学基金项目(BS2014YY009);青岛市科技局项目(14-2-3-3-nsh)

摘　　要：目的:探讨ARC orexin-A对胃传入信息以及胃运动的调控及机制。方法:采用细胞外放电记录方法,鉴定ARC orexin胃牵张敏感神经元(Gastric distention sensitive neurons,GD),并探讨ARC内orexin-A对GD神经元放电活动的影响及机制;采用ARC微量注射orexin-A和及其受体阻断剂SB334867,观察大鼠胃收缩幅度和频率的改变。结果:大鼠ARC共记录到149个GD神经元,其中GD-E神经元91个,GD-I神经元58个。ARC微量注射orexin-A,62个(62/91,68.1%)GD-E神经元兴奋性显著增加,其放电频率由4.27±0.58 Hz增加到8.46±0.95 Hz(P<0.01);39个(39/58,67.2%)GD-I神经元兴奋性也显著增强,其放电频率由4.02±0.53 Hz增加到5.43±0.57 Hz(P<0.05)。然而,ARC给予大鼠orexin-A受体拮抗剂SB334867,再给予orexin-A,orexin-A兴奋效应完全被阻断(P>0.05)。胃运动实验结果显示:在ARC注射不同浓度orexin-A,大约5 min后,大鼠胃收缩幅度和频率呈剂量依赖性增加(P<0.05~0.01)。ARC注射SB334867,可完全消除orexin-A对大鼠胃运动的兴奋效应(P<0.05)。结论:ARC orexin-A对大鼠GD神经元和胃运动有调控作用,该作用可能通过调控Orexin A受体活动实现的。Objective： To investigate the regulation and mechanism of ARC orexin-A on gastric afferent information and gastric motility. Methods： The extracellular discharge recording method： identification of ARC orexin gastric stretch sensitive neurons （Gastric distention, sensitive neurons, GD）, and to explore the effect of orexin-A on ARC activity of GD neurons and its mechanism; antagonist SB334867 by ARC microinjection of orexin-A and its receptor, observe the rat gastric conlTaction amplitude and frequency change. Results： A total of 149 GD neurons were recorded in ARC rats, of which GD-E neurons were and GD-I neurons were 58. ARC microin- jection of orexin-A, 62 （62/91, 68.1%） significantly increased the excitability of GD-E neurons, the discharge frequency from 4.27±0.58 Hz to 8.46±0.95 Hz （P〈0.01）; 39 （39/58, 67.2%） the excitability of GD-I neurons also increased significantly, the discharge frequency from 4.02±0.53 Hz to 5.43±0.57 Hz （P〈0.05）. However, ARC was given to rat orexin-A receptor antagonist SB334867, and then given orexin-A, the orexin-A effect was completely blocked （P〉0.05）. The results of gastric motility test showed that the amplitude and fre- quency of gastric contraction in rats were increased in a dose-dependent manner （P〈0.05 ~ 0.01） after ARC injection at different concen- trations of orexin-A （about 5 rain）. The effect of orexin-A on gastric motility in rats was completely eliminated by ARC injection of SB334867 （P〈0.05）. Conclusion： ARC orexin-A may regulate the activity of GD neurons and gastric motility in rats, which may be mediated by the regulation of Orexin A receptor activity.

关 键 词：OREXIN 弓状核 胃牵张敏感神经元 胃运动 

分 类 号：R-33[医药卫生] R338