Expression of c-fos in gastric myenteric plexus and spinal cord of rats with cervical spondylosis

AIM: To determine the expression of c-fos in gastric myenteric plexus and spinal cord of rats with cervical spondylosis and its clinical significance. METHODS: A cervical spondylosis model was established in rats by destroying the stability of cervical posterior column, and the cord segments C4-6 and gastric antrum were collected 3, 4 and 5 mo after the operation. Rats with sham operation were used as controls, c-fos neuronal counter-staining was performed with an immunohistochemistry method. Every third sections from C4-6 segments were drawn. The 10 most labeled c-fos-immunoreactive (Fos-IR) neurons were counted, and the average number was used for statistical analysis. The mean of Fos-IR neurons in myenteric plexus was calculated after counting Fos-IR neurons in 25 ganglia from each antral preparation, and expressed as a mean count per myenteric ganglion. RESULTS: There were a few c-fos-positive neurons in the cervical cord and antrum in the control group. There was an increased c-fos expression in model group 3, 4 and 5 mo after operation, whereas there was no significant increase in c-fos expression in the control group at 3, 4 and 5 mo. More importantly, there was a significant difference in c-fos expression between rats followed up for 3 mo and those for 5 mo in the model group (11.20±2.26 vs 27.68±4.36, P<0.05, for the cervical cord; and 11.3±2,3 vs 29.3±4.6, P<0.05, for the gastric antrum). There was no significant difference between rats followed up for 3 mo and those for 4 mo and between rats followed up for 4 mo and those for 5 mo in the model group. CONCLUSION: c-fos expression in gastric myenteric plexus was dramatically associated with that in the spinal cord in rats with cervical spondylosis, suggesting that the gastrointestinal function may be affected by cervical spondylosis. If this hypothesis is confirmed by further studies, functional gastrointestinal diseases such as functional dyspepsia and irritable bowel syndrome could be explained by neurogastroenterology.     

Toxoplasma gondii causes death and plastic alteration in the jejunal myenteric plexus

AIM:To assess the effects of ME-49 Toxoplasma gondii(T.gondii) strain infection on the myenteric plexus and external muscle of the jejunum in rats.METHODS:Thirty rats were distributed into two groups:the control group(CG)(n = 15) received 1 m L of saline solution orally, and the infected group(IG)(n=15)inoculated with 1 m L of saline solution containing500 oocysts of M-49 T.gondii strain orally.After 36 d of infection,the rats were euthanized.Infection with T.gondii was confirmed by blood samples collected from all rats at the beginning and end of the experiment.The jejunum of five animals was removed and submitted to routine histological processing(paraffin)for analysis of external muscle thickness.The remaining jejunum from the others animals was used to analyze the general population and the NADH-diaphorase,VIPergic and nitrergic subpopulations of myenteric neurons;and the enteric glial cells(S100-IR).RESULTS:Serological analysis showed that animals from the IG were infected with the parasite.Hypertrophy affecting jejunal muscle thickness was observed in the IG rats(77.02±42.71)in relation to the CG(51.40±12.34),P0.05.In addition,31.2%of the total number of myenteric neurons died(CG:39839.3±5362.3;IG:26766.6±2177.6;P0.05);hyperplasia of nitrergic myenteric neurons was observed(CG:7959.0±1290.4;IG:10893.0±1156.3;P0.05);general hypertrophy of the cell body in the remaining myenteric neurons was noted[CG:232.5(187.2-286.0);IG:248.2(204.4-293.0);P0.05];hypertrophy of the smallest varicosities containing VIP neurotransmitter was seen(CG:0.46±0.10;IG:0.80±0.16;P0.05)and a reduction of 25.3%in enteric glia cells(CG:12.64±1.27;IG:10.09±2.10;P0.05)was observed in the infected rats.CONCLUSION:It was concluded that infection with oocysts of ME-49 T.gondii strain caused quantitative and plastic alterations in the myenteric plexus of the jejunum in rats.     

Ghrelin improves delayed gastrointestinal transit in alloxan-induced diabetic mice

AIM： To investigate the effects of ghrelin on delayed gastrointestinal transit in alloxan-induced diabetic mice. METHODS： A diabetic mouse model was established by intraperitoneal injection with alloxan. Mice were randomized into two main groups： normal mice group and diabetic mice group treated with ghrelin at doses of 0, 20, 50, 100 and 200 μg/kg ip. Gastric emptying （GE）, intestinal transit （IT）, and colonic transit （CT） were studied in mice after they had a phenol red meal following injection of ghrelin. Based on the most effective ghrelin dosage, atropine was given at 1 mg/kg 15 min before the ghrelin injection for each measurement. The mice in each group were sacrificed 20 min later and their stomachs, intestines, and colons were harvested immediately. The amount of phenol red was measured. Percentages of GE, IT, and CT were calculated. RESULTS： Percentages of GE, IT, and CT were significantly decreased in diabetic mice as compared to control mice （22.9 ± 1.4 vs 28.1 ± 1.3, 33.5 ± 1.2 vs 43.2 ± 1.9, 29.5 ± 1.9 vs 36.3 ± 1.6, P 〈 0.05）. In the diabetic mice, ghrelin improved both GE and IT, but not CT. The most effective dose of ghrelin was 100 μg/kg and atropine blocked the prokinetic effects of ghrelin on GE and IT.CONCLUSION： Ghrelin accelerates delayed GE and IT but has no effect on CT in diabetic mice. Ghrelin may exert its prokinetic effects via the cholinergic pathway in the enteric nervous system, and therefore has therapeutic potential for diabetic patients with delayed upper gastrointestinal transit.     

胰岛素对糖尿病小鼠小肠功能的影响

Objective To investigate the effects of regular insulin (RI)on duodenal smooth muscle in diabetic mice. Methods Diabetes mellitus (DM) model was established by intraperitoneal injection of 150 mg/kg streptozotocin (STZ) in male BALB/c mice. The model mice were divided into DM group and DM treated with RI group with 6 each. Meanwhile, 6 normal mice were served as controls. The mice in treatment group were intraperitoneally injected with 40 U/kg of RI daily.Whereas the mice in DM and control groups were intraperitoneally injected with phosphate buffer solution (pH = 7. 40). After 6 weeks, the small intestinal transit rate of mice was determined by lavage of Indian ink. Interstitial cells of cajal (ICC) in duodenal myenteric plexus were counted using immunohistochemical staining. Slow waves of duodenal smooth muscle cells were recorded with intracellular recordings. Data were analysed by SPSS 17.0 software, and comparisons among three groups were done using LSD test. Results After intervention for 6 months, the clinical presentations,such as more water and food intake and polyuria, were improved in treatment group. The body weight was increased in treatment group [(23.33±3.13) g] compared with DM group [(15.42±1.40) g,P＜0.01] ,but dereased compared with control group [(26.78 ± 2.09) g, P＜0.05]. The level of blood glucose in DM group was significantly higher than that in control and treatment groups(P＜0.01). Small intestine transmission rate was significantly reduced in DM group than that in control and treatment groups (P＜0.01), but it was slower in treatment group than that in control group (P＜ 0. 01 ). Immunohistochemical study showed that the number of c-kit positive cells reduced obviously in DM group than that in control group and treatment group (P＜0.05), whereas it was lower in treatment group than that in control group (P ＜ 0.05). The slow wave frequency and amplitude of duodenal smooth muscle cells in DM group were reduced when compared with control and treatment groups (P＜0.01) and both were lower in treatment group than that in control group (P＜0. 01 ). Conclusion The findings indicate that DM mice have gastrointestinal dysmotility and exogenous insulin may improve small intestinal dysmotility in DM mice.     

胰岛素对糖尿病小鼠小肠功能的影响

Objective To investigate the effects of regular insulin (RI)on duodenal smooth muscle in diabetic mice. Methods Diabetes mellitus (DM) model was established by intraperitoneal injection of 150 mg/kg streptozotocin (STZ) in male BALB/c mice. The model mice were divided into DM group and DM treated with RI group with 6 each. Meanwhile, 6 normal mice were served as controls. The mice in treatment group were intraperitoneally injected with 40 U/kg of RI daily.Whereas the mice in DM and control groups were intraperitoneally injected with phosphate buffer solution (pH = 7. 40). After 6 weeks, the small intestinal transit rate of mice was determined by lavage of Indian ink. Interstitial cells of cajal (ICC) in duodenal myenteric plexus were counted using immunohistochemical staining. Slow waves of duodenal smooth muscle cells were recorded with intracellular recordings. Data were analysed by SPSS 17.0 software, and comparisons among three groups were done using LSD test. Results After intervention for 6 months, the clinical presentations,such as more water and food intake and polyuria, were improved in treatment group. The body weight was increased in treatment group [(23.33±3.13) g] compared with DM group [(15.42±1.40) g,P＜0.01] ,but dereased compared with control group [(26.78 ± 2.09) g, P＜0.05]. The level of blood glucose in DM group was significantly higher than that in control and treatment groups(P＜0.01). Small intestine transmission rate was significantly reduced in DM group than that in control and treatment groups (P＜0.01), but it was slower in treatment group than that in control group (P＜ 0. 01 ). Immunohistochemical study showed that the number of c-kit positive cells reduced obviously in DM group than that in control group and treatment group (P＜0.05), whereas it was lower in treatment group than that in control group (P ＜ 0.05). The slow wave frequency and amplitude of duodenal smooth muscle cells in DM group were reduced when compared with control and treatment groups (P＜0.01) and both were lower in treatment group than that in control group (P＜0. 01 ). Conclusion The findings indicate that DM mice have gastrointestinal dysmotility and exogenous insulin may improve small intestinal dysmotility in DM mice.     

Effect of explosive noise on gastrointestinal transit and plasma levels of polypeptide hormones

AIM: To investigate the effect of firing noise on gastrointestinal transit and probe its mechanism by measuring the levels of plasma polypeptide hormones. METHODS: A total of 64 SD rats were randomly divided into a control group and three stimulating groups. Firing noise of different intensity by sub-machine guns was used as inflicting factor. The effect of firing noise on liquid substance gastrointestinal transit and solid substance gastrointestinal transit was observed by measuring the ratio of carbon powder suspension transmitting and barium sticks transmitting respectively. Plasma levels of polypeptide hormones were measured by radio-immunoassay. RESULTS: The noise accelerated gastrointestinal transit of solid food by more than 80 db;and accelerated gastrointestinal transit of liquid food significantly by more than 120 db. Meantime, plasma levels of plasma motilin (MTL)(157.47±16.08; 151.90±17.08), somatostatin (SS)(513.97±88.77; 458.25±104.30), substance P (SP)(115.52±20.70; 110.28±19.96) and vasoactive intestinal peptide (VIP) (214.21±63.17; 251.76±97.24) remarkably changed also. CONCLUSION: Within a certain intensity range, the firing noise changes the levels of rat plasma gastrointestinal hormones, but the gastrointestinal transit is still normal. Beyond the range, the noise induces plasma hormone levels disturbance and gastrointestinal transit disorder.     

Ligustrazine alleviates gastric mucosal injury in a rat model of acute necrotizing pancreatitis

BACKGROUND: Acute necrotizing pancreatitis (ANP) leads to a systemic inflammatory response characterized by widespread leukocyte activation and, as a consequence, distant organ injury. The aim of this study was to explore the relationship between gastric microcirculatory impairment and inflammatory mediators released in rats and to evaluate the therapeutic effect of ligustrazine extracted from Rhizoma ligusticum wallichii on gastric mucosa injury in a rat model of ANP. METHODS: Ninety-six Sprague-Dawley rats were randomly divided into three groups: normal control (group C); ANP without treatment (group P); and ANP treated with ligustrazine (group T). The ANP model was induced by injection of 50 g/L sodium taurocholate under the pancreatic membrane (4 ml/kg). Group C was given isovolumetric injection of 9 g/L physiological saline by the same route. Group T was injected with ligustrazine (10 ml/kg) via the portal vein. The radioactive biomicrosphere technique was used to measure the blood flow 2 and 12 hours after the induction of ANP. Samples of the pancreas and stomach were taken to assess pathological changes by a validated histology score; meanwhile, the levels of serum interleukin-1β (IL-1β) were determined. Gastric tissues were also used to measure the level of myeloperoxidase (MPO), which is expressed intracellularly in the azurophilic granules of neutrophils. RESULTS: Blood flow in group P was significantly lower than that in group C (P<0.01). Pathological changes were significantly aggravated in group P. The gastric MPO activity in group P was significantly higher than that in group C (P<0.01). The level of serum IL-1β in group P increased more significantly than that in group C (P<0.01). Blood flow of the stomach in group T was significantlyhigher than that in group P after 2 hours (P<0.01). The pathological changes were significantly alleviated in group T. The MPO activity of group T was significantly lower than that of group P (P<0.01). Although serum IL-1β level of group T, was higher than of group C (P<0.01), it was lower than that of group P (P<0.01). There was a negative correlation between gastric blood flow and MPO activity (r=-0.983, P<0.01), and between gastric blood flow and pathological score (r=-0.917, P<0.05). CONCLUSIONS: Decreased gastric blood flow and increased inflammatory mediators can be seen early in ANP, and both are important factors for gastric and mucosal injury. Ligustrazine can ameliorate microcirculatory disorder and alleviate the damage to the pancreas and stomach.     

Involvement of parasympathetic pelvic efferent pathway in psychological stress-induced defecation

AIM:To investigate the role of the pelvic nerve pathway in stress-induced acceleration of colorectal transit and defecation in rats.METHODS:Surgical transection of rectal nerves(rectal branches of the pelvic nerve),vagotomy(Vag) or adrenalectomy(Adx) were performed bilaterally in rats.Number of fecal pellet output of these rats was measured during 1-h water avoidance stress(WAS).To evaluate the colonic transit,rats were given phenol red through the catheter indwelled in the proximal colon and subjected to WAS.After WAS session,entire colon and rectum were isolated and distribution of phenol red was measured.Distal colonic and rectal transit was evaluated using glass bead.Rats were inserted the glass bead into the distal colon and evacuation rate of the bead was measured.Neural activation was assessed by immunohistochemical staining of c-Fos and PGP9.5 in colonic whole-mount preparations of longitudinal muscle myenteric plexus(LMMP).RESULTS:In the sham-operated rats(sham op),WAS significantly increased defecation and accelerated colorectal transit with marked elevation of plasma corticosterone level.Compared with sham-operated rats,increase in the excretion of fecal pellets during WAS was significantly reduced by rectal nerve transection(RNT)(sham op:6.9 ± 0.8 vs RNT:4.3 ± 0.6,P < 0.05) or Vag(sham op:6.4 ± 0.8 vs Vag:3.7 ± 1.1,P < 0.05),although corticosterone level remained elevated.Adx-rats significantly increased the defecation despite the lower corticosterone level.Distribution pattern of phenol red showed RNT inhibited distal colonic and rectal transit accelerated by WAS,while Vag inhibited proximal colonic transit.Suppression of distal colonic and rectal transit by RNT was further confirmed by the bead evacuation rate(sham op:80.0% vs RNT:53.8%).WAS significantly increased the number of c-Fos-immunoreactive neural cells in the LMMP of the proximal and distal colon,whereas c-Fos expression was decreased by RNT in the distal colon(sham op:9.0 ± 2.0 vs RNT:4.4 ± 1.0,P < 0.05) and decreased by V     

肠道嗜铬细胞数量和5-羟色胺受体3表达在大鼠衰老过程中的变化及意义

目的 检测不同鼠龄SD大鼠肠道推进率、肠道黏膜嗜铬细胞数量和肠肌间神经丛5-羟色胺受体3(5-HT3R)的表达,探讨生理性衰老过程中肠道运动功能变化的规律及其机制. 方法 80只健康SD大鼠分为3月龄、9月龄、18月龄、24月龄及30月龄5组,每组各16只.以印度墨汁为标记物,检测大鼠的肠道推进率;采用免疫组化链霉亲和素-生物素-过氧化物酶复合物(SABC)法染色,检测大鼠空肠、回肠和结肠黏膜及黏膜下嗜铬细胞的数量以及肠肌间神经丛5-HT3R的表达.结果肠道推进率30月龄组大鼠为(52.1±9.8)%,明显低于3月龄组(67.2±13.5)%(t=7.013,P=0.001);30月龄组大鼠空肠、回肠及结肠黏膜和黏膜下嗜铬细胞数量分别为(11.1±3.0)个、(10.6±1.9)个和(10.2±4.3)个,较3月龄组(22.9±6.2)个、(25.8±7.1)个和(23.0±5.7)个减少(t=3.640,t=3.384,t=4.154,均为P<0.01);大鼠空肠和结肠的5-HT3R表达30月龄组分别为4.8±1.4和9.3±4.2,较9月龄组的8.9±1.5和14.5±5.3减少(t=3.464,t=3.003,均为P<0.01),回肠5-HT3R 30月龄组和3月龄组分别为5.0±1.3和9.0±1.7(t=4.549,P<0.001). 结论 老年大鼠肠道推进率、肠道嗜铬细胞数量及肠肌间神经丛5-HT3R表达均显著降低,并随年龄增长而逐渐明显;老年大鼠肠道运动功能的明显下降与肠嗜铬细胞数量以及肌间神经丛5-HT3R的表达显著降低有一定的相关性.     

肝衰竭大鼠胃窦胆碱能和氮能神经分布的变化分析

目的观察肝衰竭大鼠胃排空及胃窦肌间神经丛胆碱能和氮能神经的变化。方法 40只Wistar大鼠随机分为肝衰竭模型组和对照组,采用葡聚糖蓝-2000为标志物观察大鼠胃排空的变化,应用乙酰胆碱酯酶(AchE)和还原型辅酶Ⅱ硫辛酰胺脱氢酶(NADPH-d)组织化学染色及肌间神经丛全层铺片技术,观察肝衰竭大鼠胃窦肌间神经丛胆碱能和氮能神经的变化,并进行定量分析。计量资料以均数±标准差(x±s)表示,组间比较采用t检验。结果肝衰竭组大鼠胃排空明显减弱(163.00±25.68 vs 100.00±18.93,P0.01),胃窦肌间神经丛胆碱能阳性神经元数量减少,神经纤维变细,分布较稀疏,明显低于对照组(t=3.201,P0.01);氮能神经阳性神经元数量及神经纤维分布明显高于对照组(t=2.912,P0.01)。结论肝衰竭大鼠胃功能的减退与胃窦肌间神经丛胆碱能神经分布减少及氮能神经分布增加有关。     

增液汤对大鼠泻剂结肠治疗机制的研究

[目的]探讨增液汤对大黄总蒽醌引起大鼠"泻剂结肠"的治疗机制。[方法]实验分2期:第1期建立大鼠泻剂结肠模型;第2期增液汤对大鼠泻剂结肠的治疗作用;分别采用活性炭推进法检测肠道的推进功能、PGP9.5免疫组织化学染色法观察肌间神经元数量的变化和苏木精-伊红染色观察肠道病理改变,依此作为泻剂结肠模型的鉴定和增液汤疗效的观察。[结果]给予大黄总蒽醌灌胃3个月后,大鼠出现肠道推进功能明显减弱(P<0.01)、肌间神经元数目减少(P<0.05)以及黏膜下炎症细胞浸润,模型建立成功;模型治疗组加灌增液汤30d后,各项指标均有明显改善。[结论]增液汤能有效改善长期应用大黄总蒽醌引起的泻剂结肠模型大鼠的肠道传输功能,对肌间神经丛神经元的损伤具有一定的保护作用。增液汤对大黄总蒽醌引起的大鼠泻剂结肠具有治疗作用。     

替加色罗对肝硬化大鼠肠传输功能的影响

目的研究替加色罗对肝硬化大鼠肠道传输功能的影响,探讨其可能的作用机制。方法24只Wister大鼠随机分为肝硬化模型组、肝硬化替加色罗组和正常对照组,采用葡聚糖蓝-2000为胃肠内标记物,观察大鼠肠道传输的变化,同时放射免疫测定大鼠血浆：肠道组织中胃动素（MTL）、血管活性肠肽（VIP）及P物质（SP）含量的变化,乙酰胆碱酯酶（Ache）组织化学染色,观察肝硬化大鼠小肠肌间神经丛胆碱能神经的变化,并对其分布进行定量分析。结果与对照组比较,肝硬化模型组大鼠小肠动力显著减弱（P〈0.01）,血浆及空肠组织中MTL、VIP的含量明显增加,SP的含量则显著减少（P〈0.01）,小肠肌间神经丛胆碱能神经的分布明显减少（P〈0.01）;肝硬化替加色罗组大鼠小肠动力与对照组比较无明显差异,血浆及空肠组织中MTL、VIP的含量与模型组比较无明显差异,SP的含量及肠肌间神经丛胆碱能神经的分布则与肝硬化模型组差异显著（P〈0.01）。结论替加色罗对肝硬化大鼠小肠运动功能减退有明显改善作用,其机制可能与SP及肌间神经丛胆碱能神经的分布变化有关,而MTL、VIP可能未参与其作用。     

胃电节律失常大鼠胃窦肌间神经丛胆碱能神经的改变

目的：探讨大鼠胃窦肌间神经丛胆碱能神经，氮能神经含量变化与胃电节律失常的关系。方法：63例大鼠随机分为正常对照组，胃电节律失常模型组和白芍组。饲养4周后记录并分析胃电信号，测定胃窦肌间神经丛胆碱能神经含量。结果：模型组胃电节律失常明显增加，胃窦肌间神经丛胆碱能神经含量减少；经白芍治疗后，胃电节律失常明显减少，胃窦肌间神经丛胆碱能神经含量恢复正常。结论：胃窦肌间神经丛的胆碱能神经与胃电节律关系密切，当胆碱能神经减少时，胃电节律失常明显增加。     

糖尿病大鼠胃窦胆碱能神经元与胃动力障碍的关系

目的 探讨链脲佐菌素(STZ)-糖尿病大鼠胃动力障碍和胃肌间神经丛胆碱能之间的关系.方法 45只SD大鼠随机分为对照组、糖尿病组和胰岛素组.成模后16 w测定大鼠胃动力,观察胃肌间神经丛胆碱能神经元的形态变化.结果 与对照组比较,糖尿病组大鼠胃动力减弱(P<0.01),胃窦肌间神经丛胆碱能神经元计数显著降低(P<0.01).与糖尿病组相比较,胰岛素组胃动力显著增高 (P<0.05),胃窦肌间神经丛胆碱能神经元平均光密度显著增高(P<0.05),胆碱能神经元计数有改善的趋势(P>0.05).结论 STZ-糖尿病大鼠胃动力障碍可能与胃肌间神经丛胆碱能神经损伤有关,胰岛素治疗能在一定程度上改善糖尿病胃动力障碍.     

沉香化气胶囊对糖尿病大鼠小肠ICC和肌间神经丛的影响

目的:探讨沉香化气胶囊对糖尿病(diabetes mellitus,DM)大鼠小肠Cajal间质细胞(interstitial cells of Cajal,ICC)、肌间神经丛的影响.方法:将健康♂SD大鼠分为正常对照组、DM模型组、DM模型+中药组.大鼠一次性腹腔注射(ip)链脲佐菌素(STZ,60mg/kg)造模,选取成功模型,DM模型+中药组每天给予中药灌胃,模型组和正常对照组每天给予同等容量的蒸馏水,持续灌胃4wk.所有大鼠干预4wk结束后,给予印度墨汁灌胃测定小肠传输速率,利用免疫组织化学和图像分析观察十二指肠c-Kit、突触素(synaptophysin,Syn)、蛋白基因产物9.5(protein gene product 9.5,PGP9.5)的表达.结果:灌胃4wk后,DM模型+中药组小肠传输速率均比DM模型组明显增加(71.26±5.22 vs 45.52±6.42,P<0.01),仍低于对照组(71.26±5.22 vs 80.40±7.33,P<0.05);DM模型+中药组c-Kit、突触素、PGP9.5的阳性产物面积和吸光度值均比DM模型组明显增加(443.28±24.40 vs 358.83±35.03,832.33±58.78 vs 488.83±58.56,889.17±82.75 vs 445.17±64.06,0.16±0.02 vs 0.13±0.02,0.25±0.02 vs 0.16±0.01,0.24±0.02 vs 0.15±0.01,均P<0.01),仍低于正常对照组(443.28±24.40 vs 557.28±42.35,P<0.01;832.33±58.78 vs 937.67±101.23,P<0.05;889.17±82.75 vs 1050.50±90.22,P<0.01;0.16±0.02 vs 0.18±0.02,P<0.05;0.25±0.02 vs 0.29±0.03,P<0.01;0.24±0.02 vs 0.27±0.02,P<0.01).结论:沉香化气胶囊可以促进糖尿病大鼠小肠肌间神经丛c-Kit、突触素和PGP9.5的表达,提示对受损的DM大鼠小肠ICC、肌间神经丛有部分恢复作用,从而对糖尿病大鼠的胃肠动力障碍有一定的改善效应.     

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。     

大鼠泻剂结肠肠壁神经生长因子受体p75的表达及其意义

背景：神经生长因子（NGF）及其受体与肠神经系统关系密切，演剂结肠有肠壁神经丛损害，但NGF受体p75在泻剂结肠中的表达和作用尚不明确。目的：研究NGF受体p75在正常大鼠和泻剂结肠大鼠中的表达及其在泻剂结肠形成中的意义。方法：采用大黄和酚酞建立泻剂结肠大鼠模型，以墨汁推进试验测定其传输功能：采用免疫组化法对正常大鼠和泻剂结肠大鼠的结肠肠壁进行p75检测。观察其在肠壁中的分布和表达情况。结果：与对照组相比，模型组肠道传输功能明显减慢，大黄组和酚酞组黑染肠管长度和百分比（黑染肠管长度／肠管总长度）均较对照组显著减低（P〈0．01，P〈0．05）。p75存正常大鼠结肠黏膜下神经丛中呈阳性表达，在肌间神经丛中多呈弱阳性表达。大黄组中p75表达明显增强，黏膜下神经丛亦呈强阳性表达，与对照组相比有显著差异（P〈0．01）；肌间神经从中多呈阳性表达（P〈0．05）。酚酞组黏膜下神经丛呈阳性表达，肌间神绎丛3只呈阳性表达，余表现为弱阳性或阴性，与对照组相比无明显差异。结论：p75在泻剂结肠中的异常表达可能参与肠神经丛冲经元细胞的退化变性或凋亡．从而引起泻剂结肠的肠神经系统病理变化，进一步导致结肠动力异常。这种损害与长期应用刺激性泻剂有关。     

胆囊收缩素在胃电节律失常中的作用及其神经病理学机制

目的：探讨胆囊收缩素（CCK）在胃电节律失常中的作用及其神经学机制。方法：在建立胃窦肌间神经丛铺片方法的基础上,用酶组织化学与免疫细胞化学方法,观察胃电节律失常大鼠胃窦肌间神经丛内胆碱能（Ach）神经、一氧化氮合酶（NOS）神经及CCK神经的变化。结果：模型组和CCK组大鼠均出现胃电节律失常,异常节律指数及慢波频率变异系数均显著高于正常组（P＜0．01）;模型组和CCK组NOS神经显著增加,Ach神经含量显著减少（P＜0．01）。结论：外源性及内源性CCK增加,能诱发胃电节律失常。CCK通过激活NOS,产生胃电节律失常。胃窦肌间神经丛神经中CCK及NOS神经含量异常增加,Ach神经减少是发生胃电节律失常的神经病理学机制之一。