中枢外源性P物质对大鼠胃电-机械活动的影响(英文)

Effect of intraventricular administration of exogenous substance P on gastric electromechanical activity in rat

目的大鼠侧脑室给药观察中枢外源性P物质(SP)对胃电-机械活动和体表胃电活动(EGG)的影响,应用SP受体拮抗剂和阿托品探究SP作用的受体机制;比较冷应激后胃对SP和SP受体拮抗剂的动力学反应性的变化。方法雄性Wistar大鼠44只,随机分为7组:正常对照,SP,SP受体拮抗剂,阿托品,冷应激对照,冷应激+SP,冷应激+SP拮抗剂。冷应激大鼠模型制备后,进行体内慢波、快波及胃窦环行肌运动、体表胃电记录。结果①侧脑室SP给药10μL(1×10-8mol/L),能引起胃窦运动明显增强(P<0.05)。②应激使胃运动幅度极显著升高、频率加快(P<0.01),应激后大鼠对侧脑室注入P物质的胃动力学反应性较前明显增强(P<0.05)。③在本实验中,未发现侧脑室注射SP受体拮抗剂(犤D-Pro2,D-Phe7,D-Trp9犦-SubstanceP)10μL(1×10-8mol/L),有阻断内源性SP引起胃窦收缩的作用。侧脑室注射M受体阻断剂阿托品10μL(1×10-7mol/L),不能阻断脑内P物质对胃的收缩效应。结论中枢注入的P物质可以作为促进胃电-机械活动的调节因子参与中枢增强胃肠的调控。

AIM:To observed the effect of in tracereb ral ventricular administration of exogenous substance P (SP)on gastri c electromechanical activ ity and ab-dominal electrogastrography(EGG),and in vestigated the receptor mech a-nisms of SP through application of SP receptor a ntagonists and atropine.The gastrokinetic responses to SP and SP receptor antag onist after cold stre ss were also compared.METHODS:44male Wistar rats were randomly div ided into 7groups:normal control;SP;SP antagonist;A tropine;c old stress control;cold stress +SP and cold stress +SP antagonist groups.RES ULTS:①Intracerebral ventricular adminis tration of SP 10μL(1×10 -8 mol /L)significantly improved the movemen t of gastric sinus(P<0.05 );②Cold stress elevated the amplitude a nd frequency of gastric movement.The gastrokinetic respon se to intracerebral ventricular inj ection of SP in rats significantly enhanced(P<0.05)after stress compared with the baseline;③ In the experiment,there was no signi ficant effect of SP receptor antagonist( [ D -Pro 2 ,D -Phe 7 ,D -Trp 9 ]-Substance P )10μL(1×10 -8 mol /L),in blocking intrinsic SP up Atrium co ntraction.Intracerebral ve ntricu lar in-jection of M receptor blocker,Atrop ine(10μL 1×10 -7 mol /L),failed to block the gastric contraction effec t of cerebral SP.C