胃电刺激诱导大鼠延髓孤束核和迷走神经运动背核c-fos蛋白表达

背景：胃电刺激（GES）可以调控胃慢波，但其作用机制尚不完全清楚。原癌基因蛋白c—fos的表达可作为神经元功能活动的标志物。目的：以c-fos蛋白的表达为观察指标，探讨GES调控胃肌电慢波的神经机制。方法：将雌性Wistar大鼠随机分为对照组和GES组。GES以控制胃慢波为准，持续1h。分别于刺激后0．5、1、2和5h处死大鼠，以免疫组化方法观察c—fos蛋白在延髓孤束核和迷走神经运动背核中的表达。结果：对照组延髓孤束核和迷走神经运动背核仅见微量c—fos蛋白表达，GES后0．5h其表达开始增强，1h时达高峰，以后逐渐减弱。结论：GES可以调控胃肌电慢波，GES后延髓孤束核和迷走神经运动背核神经元c-fos蛋白表达阳性提示迷走神经可能参与了该调控作用。     

不同时程慢性束缚水浸应激对大鼠胃窦Cajal间质细胞超微结构的影响

目的:研究不同时程慢性束缚水浸应激大鼠胃窦Cajal间质细胞(ICC)的超微结构改变.方法:♂ SD大鼠48只随机分为6组、即实验3、7、28 d组和对照3、7、28 d组,每组8只.实验组每日束缚水浸1 h,对照组自由摄食饮水;于实验第4、8、29天晨禁食12 h后脱颈处死.取胃窦组织2块放入3%戊二醛中固定并电镜下观察ICC超微结构.结果:所有对照组ICC的超微结构均无异常改变,试验3、7、28 d各组ICC的超微结构与同期对照组比较均有明显的损害,主要表现为ICC的缝隙连接减少、细胞器减少等,以肌内ICC(ICC-MY)和肌间ICC(ICC-IM)为主:随着应激时间的延长,ICC的超微结构受损逐渐加重.结论:慢性束缚水浸应激可以损伤大鼠胃窦ICC的超微结构.     

交感神经和肌间神经丛在胃电刺激调控胃慢波中的作用

目的研究胃交感神经及肌间神经丛在电刺激调控胃慢波活动中的作用,确定胃电起博的神经机制和作用环节,为今后起搏器的深入研究打下基础。方法10只雄性wistar大鼠随机分为对照组和电刺激组,各5只。全部大鼠植入浆膜电极,电刺激组大鼠行胃电刺激至胃慢波被完全控制。植入电极组不行电刺激。采用免疫组化S P法检测并比较两组大鼠胃窦肌间神经丛和脊髓后角C fos蛋白表达。结果电刺激组大鼠胃慢波全部被完全控制,所需能量为2 70±80 .6ms ,2mA。2组大鼠脊髓中间内侧核,中间外侧核均未见C fos阳性神经元,而后角浅层均见散在C fos表达,比较无显著性差异(P >0 .0 5 )。植入电极组胃窦肌间神经丛未见C fos阳性神经元,电刺激组胃窦肌间神经丛可见C fos阳性神经元。结论适宜参数的胃电刺激可完全控制大鼠胃慢波。肌间神经丛参与胃电刺激调控胃慢波,而交感神经则无明显作用。     

外源性胃电刺激对犬胃慢波的作用

目的探讨外源性胃电刺激完全控制胃慢波的最佳刺激方法和最佳刺激参数。方法在8条比格犬的胃大弯浆膜层埋植4对电极,分4组:单导联刺激组、两导联刺激组、三导联刺激组和三导联延迟刺激组。多导联电刺激器与距胃窦上6、10和14cm的浆膜电极相连并输入不同宽度和振幅的脉冲以控制胃慢波。运用多导联胃电记录仪记录胃肌电活动。观察实验中胃慢波、脉冲宽度和振幅。结果长脉冲胃电刺激能控制胃慢波。单导联刺激组所需的最佳刺激能量最小(51.25±12.46,P<0.01)。三导联刺激组较其延迟刺激组所需的最佳刺激能量值低(P<0.01)。刺激前后胃肌电活动的主功和胃慢波的传播速度差异无统计学意义(P>0.05)。结论长脉冲胃电刺激能控制胃慢波,但对胃肌电活动的主功和传播速度无作用。单导联胃电刺激控制胃慢波所需的刺激能量最小。导联之间的延迟时间能增加控制胃慢波所需的最佳刺激能量。     

长期慢性束缚水浸应激对大鼠胃窦Cajal间质细胞数量的影响

目的:研究不同时程低强度束缚水浸应激对大鼠Cajal间质细胞(interstitial cells of Cajal,ICC)数量的影响,探讨慢性应激导致胃动力改变与ICC的相关性.方法:雄性SPF级SD大鼠48只被随机分为6组,即实验3 d、7 d、28 d组和对照3 d、7 d、28 d组,每组8只.实验组23℃水域箱内束缚水浸1h/d,对照组自由摄食饮水.4 d、8d、29d晨序贯脱颈处死.取膜胃小弯侧(ICC-1)、腺胃小弯侧(ICC-3)、腺胃大弯侧上1/3处(ICC-5)、腺胃幽门旁0.5 cm处(ICC-7)组织各一块放入固定液中,制成石蜡切片:抗c-kit免疫组织化学染色,观察不同层次ICC计数.结果:正常大鼠胃内ICC主要分布在肌内(ICC-MY)和肌间(ICC-IM),而黏膜下(ICC-SM)和深肌丛(ICC-DMP)较少.实验3 d组的各层ICC数量与对照组相比无明显差异,实验7 d和28 d组大鼠不同部位、不同层次及同一部位不同层次ICC数量明显异于同期对照组.应激时间长短对不同部位不同层次及同一部位不同层次ICC总数有明显影响,其大致规律是先正常后增加再减少,即先升高后降低.应激主要引起ICC-MY及ICC-IM数量发生变化,而本来较少的ICC-SM和ICC-DMP受影响较轻.结论:长时间低强度的慢性束缚水浸应激可以使大鼠胃窦ICC数量发生变化.     

舒胃汤对功能性消化不良大鼠胃动素及胃窦Cajal间质细胞的影响

[目的]探讨舒胃汤对功能性消化不良( functional dyspepsia,FD)肝郁脾虚证大鼠胃排空、胃动素(Motilin,MOT)、胃窦Cajal间质细胞(interstitial cells of Cajal,ICO的影响.[方法]将60只大鼠随机分为舒胃汤低剂量组(低剂量组)、舒胃汤高剂量组(高剂量组)、木香顺气丸组(中成药组)、莫沙必利组、对照组、模型组,每组10只.采用夹尾刺激方法制造FD模型,造模后第3天各组给予相应药液灌胃,对照组、模型组给予蒸馏水灌胃,持续14d.实验结束后检测胃排空,免疫组化法检测MOT水平,电镜观察胃窦ICC超微结构.[结果]模型组与对照组大鼠比较胃排空延迟,MOT水平明显升高(均P＜0.05).与模型组比较,给药各组大鼠胃排空改善(均P＜0.05);高剂量组和莫沙必利组MOT降低(均P＜0.05);透射电镜观察高剂量组胃窦部ICC与模型组比较结构明显改善,接近对照组.[结论]舒胃汤能够促进胃排空,下调MOT水平,改变胃窦ICC超微结构,恢复胃肠道运动功能可能是舒胃汤治疗FD的作用机制之一.     

胃电刺激对大鼠十二指肠部分肠神经递质释放的影响

背景：胃电刺激（GES）对胃动力的影响已引起广泛关注，但关于GES后十二指肠肌间丛神经及其递质的变化。目前所知尚少。目的：研究GES对大鼠十二指肠壁内乙酰胆碱（Ach）、一氧化氮（NO）、P物质（SP）和血管活性肠肽（VIP）释放的影响。方法：建立Wistar大鼠GES模型，将模型大鼠分为GES组（n=10）和对照组（n=6）。选用适宦的刺激参数控制GES组胃慢波，应用免疫组化方法结合图像分析技术分析十二指肠肌间神经丛胆碱能、NO能、SP能和VIP能神经活性的变化。结果：GES组十二指肠肌间神经丛胆碱乙酰转移酶（ChAT）、神经元划一氧化氮合酶（nNOS）免疫反应阳性纤维较对照组明显增多、染色增强。易见ChAT、nNOS免疫反应阳性神经节和阳性神经元细胞体；而SP、VIP免疫反应阳性纤维和末梢及其染色强度在GES后无明显变化。GES组肌删种经从ChAT、nNOS免疫反应阳性产物的平均光密度值显著高于对照组（P〈0．001），SP、VIP免疫反应阳性产物的平均光密度值则与对照绀无显著差异（P〉0．05）。结论：GES后大鼠十二指肠壁内Ach、NO释放增多，VIP、SP则无明显变化。     

正向低频串脉冲纠正逆向胃电刺激诱发的胃窦胃电过速

背景:胃电过速常由胃窦的异位起搏点引起。明确正向低频串脉冲对人工异位起搏点诱发的胃电过速的纠正作用及其相关参数对于胃电起搏的治疗应用具有重要指导意义。目的:测定低频串脉冲正向胃电刺激(FGES)完全控制高频长脉冲逆向胃电刺激(RGES)模拟异位起搏点诱发的胃电过速的最小刺激能量。方法:于比格犬胃大弯浆膜层植入4对电极,从CH4导联输入高频长脉冲RGES诱发胃电过速,刺激参数:0.3mA,300ms,9cpm(次/min)。10min后,在持续给予RGES的同时从CH1导联输入不同振幅的低频串脉冲FGES,以获得完全控制胃慢波的最小刺激能量。记录胃慢波和消化不良症状。结果:低频串脉冲FGES完全控制高频长脉冲RGES诱发的胃电紊乱所需的最小刺激能量为(149.35±50.66)smA2。与基线胃慢波相比,RGES诱发胃电过速显著增多(55.4%±25.1%对2.1%±1.1%,P=0.037),而FGES可纠正RGES诱发的胃电过速,使之恢复至基线水平。胃慢波基线期、RGES期间和FGES RGES期间实验犬消化不良症状无明显差异。结论:正向低频串脉冲能纠正由逆向高频长脉冲模拟异位起搏点诱发的胃窦胃电过速,并改善由此降低的胃动力。     

养阴和胃法和益气健脾法对糖尿病胃轻瘫大鼠胃动力及Cajal间质细胞影响的比较研究

[目的]探讨并比较养阴和胃法和益气健脾法对糖尿病胃轻瘫(DGP)大鼠胃动力及Cajal间质细胞(ICC)的影响.[方法]SD大鼠随机均分为正常对照组、DGP模型组、养阴组及益气组.静脉注射链脲佐菌素(STZ)建立大鼠DGP模型,正常对照组和DGP模型组注射等量蒸馏水,养阴组及益气组分别用养阴和胃中药与益气健脾中药灌胃.酚红灌胃实验测定胃排空率,免疫组化法检测胃窦肌间c-kit阳性ICC的含量.[结果]DGP模型组大鼠的胃排空率、胃血流量、胃窦ICC含量均显著低于正常对照组(P＜0.05),表明DGP大鼠模型建立成功.各给药组大鼠的胃排空率、胃血流量、胃窦ICC含量均优于DGP模型组(P＜0.05),其中养阴组大鼠的胃排空率、胃血流量、胃窦ICC含量较益气高剂量组略有增高,但差异无统计学意义.[结论]养阴和胃与益气健脾中药均可通过调节ICC的数量,改善PGP大鼠的胃肠起搏功能,促进胃动力,且养阴和胃法作用优于益气健脾法.     

调中颗粒对胃肌间Cajal间质细胞功能及数量的影响

[目的]观察功能性消化不良（FD）大鼠胃肌间Cajal间质细胞（ICC）超微形态结构、分布特点和密度变化,探讨调中颗粒治疗FD的机制。[方法]将40只大鼠随机分为5组,各8只,除正常组外,其余采用夹尾法制备FD模型,胃电图的方法检测造模是否成功,电镜观察胃肌间ICC的超微结构。酪氨酸激酶受体c-kit免疫组化法观察不同药物治疗后胃肌间阳性ICC的分布和水平变化。[结果]模型组大鼠胃电参数低于正常组（P〈0．05）;ICC的超微结构证实ICC与胃平滑肌运动具有密切相关性;调中颗粒能明显升高胃窦ICC水平（P〈0．05）,优于多潘立酮（P〈0．05）。[结论]调中颗粒能通过调节ICC的分布和数量,升高胃窦ICC的表达,促进胃蠕动,改善FD大鼠胃电节律。调中颗粒疗效优于半夏泻心汤和多潘立酮,具有整体调节作用。     

Vagal Afferent Is Involved in Short-Pulse Gastric Electrical Stimulation in Rats

This study investigated the effect of gastric electrical stimulation (GES) on vagal activity and its possible vagal afferent-mediated mechanisms. Sixty rats implanted with gastric serosal electrodes were divided into six groups (control, vehicle, local capsaicin, perivagal capsaicin, systemic capsaicin, and vagotomy). GES with six sets of parameters was performed in the control group; and GES with one set of effective parameters was performed in the other five groups. Spectral analysis of heart rate variability was used to assess vagal activity. Regular gastric slow waves were recorded in the control rats with a frequency of 4.8 cycles/min. Vagotomy significantly reduced the frequency of the gastric slow wave but did not induce dysrhythmia. Capsaicin did not alter the gastric slow wave. Short-pulse (300-microsec) GES significantly increased vagal activity at a frequency four times the intrinsic slow-wave frequency. Stimulation at a lower frequency or with a long pulse (300 msec) had no effect on vagal activity. Vagotomy or capsaicin administered perivagally, systemically, or locally abolished the effect of GES on the vagal activity. GES with short but not long pulses is capable of altering vagal activity. This effect is mediated by capsaicin-sensitive vagal afferent fibers.     

Long-pulse gastric electrical stimulation protects interstitial cells of Cajal in diabetic rats via IGF-1 signaling pathway

AIM: To investigate the effects of different parameters of gastric electrical stimulation(GES) on interstitial cells of Cajal(ICCs) and changes in the insulin-like growth factor 1(IGF-1) signal pathway in streptozotocininduced diabetic rats.METHODS: Male rats were randomized into control, diabetic(DM), diabetic with sham GES(DM + SGES), diabetic with GES1(5.5 cpm, 100 ms, 4 m A)(DM + GES1), diabetic with GES2(5.5 cpm, 300 ms, 4 m A)(DM + GES2) and diabetic with GES3(5.5 cpm, 550 ms, 2 m A)(DM + GES3) groups. The expression levels of c-kit, M-SCF and IGF-1 receptors were evaluated in the gastric antrum using Western blot analysis. The distribution of ICCs was observed using immunolabeling for c-kit, while smooth muscle cells and IGF-1 receptors were identified using α-SMA and IGF-1R antibodies. Serum level of IGF-1 was tested using enzyme-linked immunosorbent assay. RESULTS: Gastric emptying was delayed in the DM group but improved in all GES groups, especially in the GES2 group. The expression levels of c-kit, M-SCF and IGF-1R were decreased in the DM group but increased in all GES groups. More ICCs(c-kit+) and smooth muscle cells(α-SMA+/IGF-1R+) were observed in all GES groups than in the DM group. The average level of IGF-1 in the DM group was markedly decreased, but it was up-regulated in all GES groups, especially in the GES2 group. CONCLUSION: The results suggest that long-pulse GES promotes the regeneration of ICCs. The IGF-1 signaling pathway might be involved in the mechanism underlying this process, which results in improved gastric emptying.     

突触在胃起搏调控胃慢波活动中的作用

目的研究胃窦肌间神经丛中突触素（synaptophysin,Syn）分布及其mRNA和蛋白的表达,探讨突触素在胃起搏机制中的作用。方法通过手术建立Wistar大鼠胃起搏模型（近远端胃各缝制一对电极）,分为起搏组（GES组,n=10）和对照组（n=6）。应用免疫组化染色观察GES组和对照组胃窦间神经丛中突触素分布,采用逆转录聚合酶链反应（RT-PCR）和Western blot分别检测GES和对照组胃窦肌间神经丛中Syn mRNA和蛋白的表达量,以恒定表达的β-actin作为内参照。分别计算Syn mRNA与β-actinmRNA、Syn蛋白与β-actin蛋白表达积分光密度值的比值（Syn/β-actin）,以反映组织中Syn mRNA和蛋白的相对表达量。结果与对照组相比,GES组肌间神经丛中Syn免疫反应阳性产物分布显著增多（806.421±342.135vs448.3±261.467,P〈0.05;0.019±0.008vs0.010±0.005,P〈0.05）。RT-PCR研究显示GES组Syn mRNA表达显著强于对照组,GES组syn/β-actin比值明显较对照组增加（0.146±0.0 28vs0.082±0.025,P〈0.05）;Western blot研究显示GES组Syn蛋白表达也较对照组明显增强,两组Syn/β-actin比值比较差异有统计学意义（0.502±0.098vs0.298±0.018,P〈0.05）。结论胃起搏后胃肌间神经丛内突触素分布增多,突触素mRNA和蛋白表达量明显增加,表明胃窦肌间神经丛内突触可能在胃起搏中发挥了重要作用。     

短波胃电刺激对大鼠下丘脑促皮质激素释放因子和强啡肽能神经的影响

研究高频短波胃电刺激对大鼠下丘脑促皮质激素释放因子（CRF）和强啡肽表达的影响,探讨高频短波胃电刺激治疗消化不良的可能机制。方法 10只SD大鼠随机分为对照组和胃电刺激组,每组5只,均于胃浆膜面植入刺激电极一对。对照组给予假性胃电刺激,胃电刺激组给予短波胃电刺激（频率20次/min,波宽300μs,波幅2 mA）,1 h后取各组大鼠下丘脑组织做CRF、强啡肽和c-fos蛋白免疫组化染色,比较各组蛋白表达变化。结果胃电刺激组大鼠下丘脑c-fos和强啡肽阳性神经显著高于对照组（P〈0.05）,而下丘脑CRF阳性神经显著低于对照组（P〈0.05）。结论短波胃电刺激增加下丘脑c-fos和强啡肽阳性神经的表达,并抑制CRF能神经的表达,提示下丘脑强啡肽能神经和CRF能神经参与短波胃电刺激的神经调控。     

短波胃电刺激对大鼠孤束核及下丘脑c-fos表达的影响及其机制

目的 探讨肠肌间神经丛及中枢神经系统相关核团(孤束核及下丘脑)是否参与介导外源性短波胃电刺激调控中枢感觉功能.方法 雄性Wistar大鼠15只,分为对照组、胃电刺激组、去肠肌间神经丛组,均于胃底、胃体交界处植入一对电极,去肠肌间神经丛组大鼠同时胃浆膜面予苯扎氯胺处理,后两组均予短波胃电刺激,持续30 min.SP免疫组化法观察延髓孤柬核及下丘脑c-fos表达.结果 胃电刺激组和去肠肌间神经丛组大鼠每高倍视野下孤束核处c-fos阳性神经元数量分别为(71.6±7.4)和(63.4±10.8)个,下丘脑处则分别为(224.2±47.3)和(249.1±44.0)个,两组间差异无统计学意义(P＞0.05),但均显著高于对照组[(36.4±8.6)和(90.2±47.3)个,P值均＜0.05].结论 孤束核及下丘脑可能是介导短波胃电刺激治疗作用的中枢核团,而肠神经系统不参与介导此作用.     

Feasibility of gastric electrical stimulation by use of endoscopically placed electrodes

BACKGROUND: Gastric electrical stimulation (GES), which has been reported to have therapeutic potentials for gastroparesis and obesity, involves the surgical placement of electrodes with the patient under general anesthesia. New methods are needed for implanting GES electrodes in a safer and more feasible way. OBJECTIVE: Our purpose was to investigate the safety and feasibility of placing electrodes endoscopically for GES. DESIGN AND SETTING: A pilot study. SUBJECTS: Six female hound dogs that weighed 13 to 22 kg. INTERVENTIONS: Endoscopically placed electrodes passed through the abdomen and the stomach wall. MAIN OUTCOME MEASUREMENTS: The study was performed in dogs surgically implanted with gastric serosal electrodes and endoscopically implanted electrodes. The experiment consisted of a 30-minute baseline, a 30-minute GES, and a 30-minute recovery. GES was performed through endoscopically placed electrodes. Gastric slow waves were simultaneously recorded with the serosal electrodes and the endoscopically placed electrodes. RESULTS: (1) The slow wave frequency recorded from the endoscopically placed electrodes was significantly correlated with that from the serosal electrodes (r = 0.97, P < .002). (2) GES through the endoscopically placed electrodes was able to entrain gastric slow waves. (3) No gastric leakage into the abdominal cavity was noted and the dogs were healthy and comfortable. (4) The endoscopically placed electrodes remained for 2 to 3 weeks. LIMITATIONS: The fixation of the electrodes needs to be improved for longer-term uses. CONCLUSIONS: GES may be accomplished without surgery by inserting the electrode wire through the abdomen under endoscopy. The study results indicate that the endoscopically placed electrodes are effective for GES and do not result in any adverse events.     

Effect of two-channel gastric electrical stimulation with trains of pulses on gastric motility

AIM： To investigate the effect of two-channel gastric electrical stimulation （GES） with trains of pulses on gastric emptying and slow waves.METHODS： Seven dogs implanted with four pairs of electrodes and equipped with a duodenal cannula were involved in this study. Two experiments were performed.The first experiment included a series of sessions in the fasting state with trains of short or long pulses, each lasted 10 min. A 5-min recording without pacing was made between two sessions. The second experiment was performed in three sessions （control, single-channel GES, and two-channel GES）. The stimulus was applied via the 1st pair of electrodes for single-channel GES （GES via one pair of electrodes located at 14 cm above the pylorus）, and simultaneously via the 1st and 3rd channels for two-channel GES （GES via two pairs of electrodes located at 6 and 14 cm above the pylorus）, Gastric liquid emptying was collected every 15 min via the cannula for 90 min.RESULTS： GES with trains of pulses at a pulse width of 4 ms or higher was able to entrain gastric slow waves. Two-channel GES was about 50% more efficient than single-channel GES in entraining gastric slow waves. Two-channel but not single-channel GES with trains of pulses was capable of accelerating gastric emptying in healthy dogs. Compared with the control session, two-channel GES significantly increased gastric emptying of liquids at 15 rain （79.0% ± 6.4% vs 61.3% ± 6.1%, P 〈 0.01）, 30 min （83.2% ± 6.3 % vs 68.2% ± 6.9%, P 〈 0.01）, 60 min （86.9% ± 5.5 % vs 74.1% ± 5.9%, P 〈 0.01）, and 90 rain （91.0% ± 3.4% vs 76.5% ± 5.9%, P 〈 0.01）.CONCLUSION： Two-channel GES with trains of pulses accelerates gastric emptying in healthy dogs and may have a therapeutic potential for the treatment of gastric motility disorders.     

胃起搏对大鼠胃窦肌间神经丛5-羟色胺能神经的影响

背景:胃起搏治疗胃动力障碍性疾病已引起广泛关注,但其作用机制尚不清楚。目的:观察胃起搏后胃窦肌间神经丛5-羟色胺(5-HT)能神经的活性变化,探讨胃起搏促胃动力作用的神经化学机制。方法:建立Wistar大鼠胃起搏模型,将大鼠分为起搏组(n=10)和对照组(n=6)。选用适宜的起搏参数以控制起搏组胃电慢波,1h后取胃窦组织,以免疫组化方法结合图像分析技术分析5-HT免疫反应阳性产物的分布、数量和免疫反应强度。结果:对照组大鼠5-HT免疫反应阳性神经纤维以肌间神经丛和节间束中稍多,神经节内阳性神经细胞体少见。起搏组大鼠胃窦组织5-HT免疫反应阳性神经纤维较对照组明显增多,神经节内阳性神经细胞体和带膨体的神经纤维也明显增多,免疫反应增强;肌间神经丛5-HT免疫反应阳性产物面积和平均光密度值均显著高于对照组(P<0.001)。结论:胃起搏后,胃窦肌间神经丛5-HT免疫反应阳性神经纤维和神经细胞体分布增多,5-HT能神经活性增强,表明5-HT能神经可能参与了胃起搏的促胃动力作用。