神经生长因子在多次盐酸灌注食管气道高反应豚鼠肺组织中的表达

目的 观察多次盐酸灌注豚鼠食管对呼吸道黏膜内神经生长因子(nerve growth factor,NGF)物质表达的影响.方法 将20只豚鼠按随机数字表法分为2组,每组10只.①模型组:用盐酸氯胺酮将豚鼠轻度麻醉,将5F胃管插入豚鼠食管至食管中下端,灌注含0.5%胃蛋白酶的盐酸(0.1 mol/L,8滴/min,20 min/d),连续灌注14 d;②对照组:用PBS代替盐酸灌注食管,方法同上.用免疫组织化学方法测定两组豚鼠肺组织NGF的免疫反应变化;用免疫印迹法(Western blotting)检测肺组织NGF的免疫反应变化;Metamoph图像分析系统对结果进行分析.结果 免疫组织化学结果显示(染色反应强度用灰度值表示):模型组豚鼠气管和细支气管黏膜内NGF物质阳性反应的平均灰度值明显地低于对照组[(108.46±9.89)vs(135.86±4.01)](P<0.01).Western blotting显示NGF在模型组豚鼠的肺内平均相对光密度值明显强于对照组[(1.415±0.155)vs(0.550±0.039)](P<0.01).结论 多次盐酸灌注豚鼠食管后呼吸道黏膜内NGF物质表达明显增多,提示NGF可能参与胃食管反流性呼吸系统疾病的发病过程.     

豚鼠食管多次盐酸灌注对呼吸道黏膜P物质表达的影响

目的 观察多次盐酸灌注豚鼠食管对呼吸道黏膜内P物质表达的影响.方法 将20只豚鼠按随机数字表法分为模型组和对照组,每组10只.模型组用盐酸氯胺酮将豚鼠轻度麻醉,将5 F胃管插入豚鼠食管至食管中下端,灌注含0.5%胃蛋白酶的0.1 mol/L盐酸(8滴/min,20 min/d),连续灌注14 d.对照组用PBS代替盐酸灌注食管,方法同模型组.在末次灌注后24 h,所有豚鼠应用氯化乙酰胆碱按浓度倍增法(3.125、6.25、12.5、25、50及100μg/kg)依次颈外静脉注射进行支气管激发实验;取左肺组织行HE染色,用抗P物质抗体行免疫组织化学染色.结果 随着乙酰胆碱浓度的成倍递增,模型组与对照组的肺阻力均增加,当浓度达到25μg/kg以上时,模型组与对照组的肺阻力比较差异有统计学意义(t值分别为43.057、51.410和57.359,均P<0.01);免疫组织化学结果显示(染色反应强度用灰度值表示),模型组豚鼠气管和细支气管黏膜内P物质阳性反应的平均灰度值(分别为7±4、85±5)明显低于对照组(分别为16±4、102±6)(t值分别为3.44、2.16,均P<0.01).结论 多次盐酸灌注豚鼠食管后呼吸道黏膜内P物质表达明显增多,提示神经源性炎症可能参与胃食管反流性疾病的发病过程.     

过氧亚硝基阴离子在哮喘豚鼠气道高反应性中的作用

目的 探讨哮喘豚鼠内过氧亚硝基阴离子（ＯＮＮＯＯ＾－）的生成及其在哮喘气道高反应性形成中的作用。方法 １８只哮喘豚鼠模型随机分为３组：（１）哮喘组（６只）：用１０％卵蛋白１ｍｌ腹腔注射液致敏,２周后用１％卵蛋白超声雾化吸入复制豚鼠哮喘模型。（２）哮喘加氨基胍（ＡＧ）组（６只）：该喘同哮喘组,在每次诱喘前１ｈ腹腔注射ＡＧ１０ｍｇ／ｋｇ。（３）正常对照组（６只）：用生理盐水代替诱喘剂。每组哮喘豚鼠均用     

神经生长因子在哮喘发病中的作用

近年来的研究发现哮喘发病机制中，免疫细胞和神经元之间存在着广泛的联系。生长因子（NGF）由免疫细胞产生，通过调控神经元的可塑性，介导气道高反应性，并参与气道炎症形成的过程，认为NGF是哮喘免疫神经发病机制的重要介质。     

食管感觉性受体信号通路在食管高敏感发生中的作用

胃食管反流病（GERD）是一种常见的消化道疾病,烧心和反酸是GERD的典型症状。近年诸多研究显示食管高敏感是烧心症状发生、发展的重要病理生理机制,瞬时受体电位香草酸亚型1(TRPV1)、前列腺素E2受体1 (EP1)、蛋白酶活化受体2(PAR2)、瞬时受体电位M8 (TRPM8)在食管高敏感的发生机制中起关键作用。本文就食管感觉性受体信号通路在食管高敏感发生中的作用作一综述。     

神经生长因子在哮喘发病中的作用

近年来的研究发现哮喘发病机制中 ,免疫细胞和神经元之间存在着广泛的联系。神经生长因子(NGF)由免疫细胞产生 ,通过调控神经元的可塑性 ,介导气道高反应性 ,并参与气道炎症形成的过程 ,认为NGF是哮喘免疫神经发病机制的重要介质     

十二指肠胃食管反流在胃食管反流病中的作用

目的　研究十二指肠胃食管反流 (DGER)在胃食管反流病发病机制中的作用及其对非糜烂性反流病 (NERD)的诊断价值。方法　 95例患者根据内镜检查的结果分为反流性食管炎和NERD组 ,对其均进行 2 4h食管 pH和胆汁联合监测。 结果　反流性食管炎患者DGER的各项指标 :吸光度值 >0 14时间百分比 (% )、总反流次数和反流 >5min的次数分别为 19 0 5± 2 3 4 4、30 5 6±34 0 4和 5 90± 6 37,均显著高于NERD组相应的 7 2 6± 11 0 8、15 6 8± 2 0 92和 2 5 9± 3 5 7(P <0 0 5 ) ,而酸反流差异无显著性 ,随着反流性食管炎的程度加重DGER发生率增高 ;18 2 %的NERD患者存在单纯DGER ,联合胆汁监测可使NERD诊断阳性率由 6 5 9%升高到 84 1%。结论　DGER可以单独发生 ,在引起反流性食管黏膜损伤或症状方面都有作用 ,2 4h食管 pH和胆汁联合监测有助于NERD的诊断。     

慢性支气管炎和哮喘中的胃食管反应

近年来认识到病理性胃食管酸反流(GER)与呼吸系疾病有关,发现30 %～85%的慢性咳嗽和哮喘并存GER[1～3].国内对此研究匮乏,我们用24小时食管p H监测对此进行了前瞻性研究,以了解国内慢性支气管炎和支气管哮喘者中GER发生率、反流类型及其食管上段的反流.     

无效食管动力在非糜烂性酸反流病中的临床意义

目的　探讨无效食管动力（ineffective esophageal motility,IEM）在非糜烂性酸反流相关疾病中的作用、成因及第四版芝加哥分类标准（CC v4.0）对IEM诊断的影响。方法　2018年1月—2020年1月,因酸反流相关症状在北京友谊医院消化内科行胃镜检查提示食管黏膜或结构无异常改变,且行食管高分辨测压检测和24 h食管pH值监测的63例患者纳入病例对照研究。根据食管高分辨测压检测结果,分别采用第三版芝加哥分类标准（CC v3.0）和CC v4.0进行分组,分为IEM组和正常动力组。主要对比分析同版分类标准下2组的食管高分辨测压检测结果、24 h食管pH值监测结果和最终诊断,以及不同版分类标准下同一观察指标2组间的变化程度。结果　63例患者中,非糜烂性胃食管反流病（non?erosive gastroesophageal reflux disease,NERD）14例、反流高敏感（reflux hypersensitivity,RH）19例、功能性烧心（functional heartburn,FH）30例。采用CC v3.0时,IEM组20例,其中NERD 9例、RH 5例、FH 6例;正常动力组43例,其中NERD 5例、RH 14例、FH 24例。采用CC v4.0时,IEM组16例,其中NERD 7例、RH 4例、FH 5例;正常动力组47例,其中NERD 7例、RH 15例、FH 25例。采用CC v3.0时,IEM组食管酸暴露时间［3.45（1.55,6.40）%比1.20（0.40,2.30）%,Z=-2.940,P=0.003］、DeMeester评分［13.8（5.8,21.4）分比5.3（2.9,10.0）分,Z=-2.851,P=0.004］明显高于正常动力组,食管下括约肌静息压［10.15（7.52,13.65）mmHg（1 mmHg=0.133 kPa）比15.40（11.20,21.60）mmHg,Z=-3.241,P=0.001］、4 s完整松弛压［（3.79±0.57）mmHg比（6.05±0.50）mmHg,t=2.727,P=0.008］、远端收缩积分［334.65（208.25,438.92）mmHg·s·cm比1 258.70（919.00,1 750.10）mmHg·s·cm,Z=-6.305,P<0.001］明显低于正常动力组。采用CC v4.0时,IEM组食管酸暴露时间、DeMeester评分亦均明显高于正常动力组（P均<0.05）,食管下括约肌静息压、4 s完整松弛压、远端收缩积分亦均明显低于正常动力组（P均<0.05）,另外,食管上括约肌静息压明显低于正常动力组［34.60（21.50,48.05）mmHg比49.67（36.75,61.10）mmHg,Z=-2.140,P=0.032］。结论　在非糜烂性酸反流相关疾病患者中,IEM与抗反流屏障功能受损相关,且与食管酸暴露相关。相比CC v3.0,CC v4.0在一定程度上可使得IEM患者异质性减少。     

GerdQ量表在胃食管反流病诊断中的应用

目的探讨胃食管反流病量表(GerdQ)应用于诊断胃食管反流病(GERD)的价值。 方法对2013年6月至2014年10月在新疆维吾尔自治区人民医院就诊收住并存在反流相关症状的疑似胃食管反流病的1 000例患者进行问卷调查,按照烧心、反流、上腹痛、恶心、睡眠障碍、是否服用OTC药物等6项症状的发作频率进行评分。采用上消化道内镜检查及食管24 h pH监测作为GERD诊断的标准,并与GerdQ分值进行比较,最后计算出诊断GERD的临界值,进而分析GerdQ量表在GERD中的诊断价值。 结果GERD组的GerdQ积分主要集中于7～12分,非GERD组主要集中于6分以下,差异有统计学意义(P<0.05)。以GerdQ分值8为临界值,Youden指数最大(0.51),ROC曲线下的面积0.765,其敏感度为81.32%,特异性为70.21%,阳性预测值83.24%,阴性预测值61.53%。 结论GerdQ量表简单、易行,可作为临床上筛查诊断GERD的有效方法。     

Duodenogastric reflux causes growth stimulation of foregut mucosa potentiated by gastric acid blockade

We investigated whether duodenogastric reflux (DGR) together with gastroesophageal reflux causes growth stimulation of the foregut mucosa and if additional gastric acid suppression enhances the effect of DGR. DGR was induced in rats using a split gastroenterostomy. A cardiomyotomy was performed across the gastroeophageal junction in order to enhance reflux into the esophagus. DGR rats were divided into six subgroups: DGR, DGR + truncal vagotomy, DGR + omeprazole, DGR + gastrin receptor blockade, DGR + omeprazole + gastrin receptor blockade, and DGR + gastrin. Two sham groups, one with and one without omeprazole treatment, served as controls. DGR significantly increased the weight and DNA content of the esophageal and gastric mucosa, which was further enhanced by vagotomy or omeprazole. Histology revealed foveolar hyperplasia in the stomach and esophageal mucosal hyperplasia in these groups. In addition, severe esophagitis was found in the DGR group receiving omeprazole. Omeprazole without DGR had no growth-stimulating effect on the foregut mucosa. DGR-induced growth stimulation was accompanied by hypergastrinemia. Increased growth in the stomach but not the esophagus was inhibited by gastrin receptor blockade. Gastrin administration did not result in enhancement of DGR-induced growth stimulation of the foregut mucosa. It is concluded that DGR, often present in severe reflux esophagitis, causes mucosal growth of the foregut of rats. This trophic response may explain why severe reflux esophagitis is associated with an increased risk of esophageal adenocarcinoma. DGR-induced growth stimulation of the foregut is potentiated by gastric acid suppression, suggesting that chronic antisecretory medication in gastroesophageal reflux may not always be advisable. Omeprazole + DGR caused severe esophageal damage, which may explain why antisecretory medication may fail to heal severe reflux esophagitis.     

Two distinct insulin-related molecules in the guinea pig: immunological and biochemical characterization of insulin-like immunoactivity from extrapancreatic tissues of the guinea pig

Summary In this study we extracted guinea pig brain and testis with; the extract was adsorbed to and eluted from cartridges (the Sep-Pak C 18 procedure). We found this procedure superior for recovering crystalline insulin added to buffers or tissues, and for recovering endogenous insulin from plasma, but inferior for recovery of insulin from tissues. However, we did find rat/pork type-insulin in guinea pig brain and testis (5–50 pg/g wet weight tissue). Our results with the Sep-Pak C18 procedures were reproduced by four other laboratories (who found 4–60 pg/g wet weight of tissue) and similar findings were also obtained by an independent investigator. Thus, we conclude that extrapancreatic tissues of guinea pigs have a second type of insulin-related material that is more typical of other mammalian insulins, but that the amount recovered is dependent upon the extraction procedure utilized.     

Effects of insulin on the acetylcholine-induced hyperpolarization in the guinea pig mesenteric arterioles

Background: Insulin induces endothelium-dependent vasodilatation, which may be casually related to the insulin resistance and hypertension. Endothelium-derived nitric oxide (NO) is the most important mechanism of insulin-induced vasodilatation, and a possible contribution of endothelium-derived hyperpolarizing factor (EDHF) is also considered. Attempts were made to observe the effects of insulin on acetylcholine (ACh)-induced hyperpolarization in the submucosal arteriole of the guinea pig ileum, the objective being to investigate possible involvement of EDHF in the actions of insulin. Methods: Conventional microelectrode techniques were applied to measure the membrane potential of smooth muscle cells in the submucosal arteriole. EDHF-induced hyperpolarization was elicited by ACh in the presence of both N^ω-nitro- -arginine ( -NNA) (100 μM) and diclofenac (1 μM). Results: The resting membrane potential was −70.9 mV, and Ba²⁺ (0.5 mM) depolarized the membrane to −33.0 mV. Insulin (10 μU/ml to 100 mU/ml) did not change the membrane potential in the absence or presence of Ba²⁺. In the presence of Ba²⁺, ACh (3 μM) hyperpolarized the membrane with two components, an initial large hyperpolarization followed by a slow and small one. Low concentration of insulin (100 μU/ml) did not alter the ACh-induced hyperpolarization. High concentration of insulin (100 mU/ml) shortened the time required to reach the peak amplitude and tended to increase the peak amplitude of the ACh-induced hyperpolarization. Conclusions: The data show that insulin enhances the ACh-induced hyperpolarization in the submucosal arterioles of the guinea pig ileum. The results suggested that EDHF also accounts for one of the endothelial factors involved in the insulin-induced vasodilatation.     

Regulation of voltage-gated cardiac sodium current by epidermal growth factor receptor kinase in guinea pig ventricular myocytes

Voltage-gated cardiac fast sodium channel current (I(Na)) plays a critical role in the initiation and propagation of the myocardial action potential, and regulation of cardiac I(Na) by protein tyrosine kinases (PTKs) is not well documented, though it is known that ion channels are among the targets of PTKs. The present study was therefore designed to investigate whether/how cardiac I(Na) was modulated by PTKs in guinea pig ventricular myocytes using whole-cell patch clamp and immunoprecipitation and Western blotting approaches. It was found that cardiac I(Na) was enhanced by epidermal growth factor (EGF), and the effect was antagonized by the selective epidermal growth factor receptor (EGFR) kinase inhibitor tyrphostin AG556 while potentiated by orthovanadate (a protein tyrosine phosphatase (PTP) inhibitor). In addition, AG556 inhibited, while orthovanadate increased I(Na), and the inhibition of I(Na) by AG556 was antagonized by orthovanadate. Immunoprecipitation and Western blotting analysis demonstrated that tyrosine phosphorylation level of cardiac sodium channels was enhanced by EGF or orthovanadate, and reduced by AG556. The AG556-induced reduction of phosphorylation level was significantly reversed by orthovanadate. Our results demonstrate the novel information that EGFR kinase enhances, and PTPs reduce native cardiac I(Na) in guinea pig ventricular myocytes.     

Pulmonary hypertension induced by amosite asbestos: A physiological and morphologic study in the guinea pig

Although there is increasing evidence that mineral dust exposure will produce obstructive lung disease, there is little information on the effects of mineral dust on the pulmonary vascular system. To examine whether exposure to amosite asbestos would affect the pulmonary vasculature and produce pulmonary hypertension, we instilled 5 mg amosite asbestor intratracheally into guinea pigs. After periods of 3 and 6 months, we examined their pulmonary and pulmonary vascular function, and compared these data to those obtained from groups of control animals. We found that, at both time periods, there was pulmonary arterial hypertension, with alteration of the vascular pressure-flow relationships. This was accompanied by abnormalities in the structure of the small pulmonary arterioles. The animals also showed airflow obstruction, with air trapping and an upward shift of the pressure-volume curve. There was evidence of emphysema, and the animals were moderately hypoxic. We found no consistent increase in inflammatory cells either in lavage or peripheral blood, and the histamine dose-response curves were similar in control and asbestos-exposed animals at 6 months. We conclude that intratracheal instillation of asbestos in the guinea pig produces pulmonary hypertension associated with modest hypoxia, emphysema, and airflow obstruction. Whether pulmonary hypertension reflects emphysema-induced hypoxia and loss of vascular bed, or is related to the brief but intense inflammatory infiltrate induced by asbestos, is unclear.     

母牛分枝杆菌菌苗对哮喘豚鼠肺组织Eotaxin mRNA表达的影响

目的研究母牛分枝杆菌菌苗对哮喘豚鼠肺组织Eotaxin mRNA表达的影响。方法30只豚鼠随机分为生理盐水组、哮喘组及母牛分枝杆菌菌苗组，每组lO只。应用卵白蛋白（OVA）建立哮喘模型，母牛分枝杆菌菌苗组每只豚鼠在OVA致敏前10d肌注22．5峭母牛分枝杆菌菌苗。最后一次激发后，计数支气管肺泡灌洗液（BALF）中炎症细胞，观察肺组织病理学改变，应用原位杂交方法检测肺组织Eotaxin mRNA的表达。结果母牛分枝杆菌菌苗组豚鼠BALF中嗜酸粒细胞数量显著低于哮喘组（P〈0．01），肺组织哮喘炎症反应明显轻于哮喘组，肺组织Eotaxin mRNA表达（OD值）显著低于哮喘组（P〈0．01）。结论母牛分技杆菌菌苗能减少哮喘豚鼠BALF及肺组织嗜酸粒细胞数量，与其抑制Eotaxin mRNA在哮喘豚鼠肺组织的表达有关。     

阿米卡星对豚鼠耳蜗毛细胞磷酸化JNK表达的影响

目的 探讨阿米卡星(AMK)对豚鼠耳蜗毛细胞磷酸化c-Jun氨基末端激酶(JNK)表达的影响及耳毒性机制.方法 豚鼠随机分为对照组、AMK 3 d组、AMK 7 d组和AMK 11 d组,AMK组分别连续肌肉注射AMK(400 mg/kg)3、7 d和11 d,对照组肌肉注射等量生理盐水.应用免疫组织化学(SABC)法和显微图像分析技术观察磷酸化JNK(p-JNK)在豚鼠耳蜗毛细胞中的表达,同时结合听觉脑干反应(ABR)测试观察用药前后豚鼠听力的变化.结果 对照组豚鼠耳蜗毛细胞中无p-JNK的表达,而注射AMK后,在豚鼠耳蜗中可见p-JNK表达,并且随着给药时间的延长,p-JNK的表达亦明显增强,同时ABR阈移显著增大,与对照组比较均有显著性差异(P＜0.01).结论 p-JNK可在AMK致毒豚鼠耳蜗毛细胞中表达,且其表达与听力变化高度相关,提示JNK信号通路可能参与了AMK的耳毒性损伤.     

Acute effects of amiodarone on membrane properties,refractoriness, and conduction in guinea pig papillary muscles

Summary Amiodarone has potent and complex antiarrhythmic effects associated with a rare incidence of proarrhythmia. For a comprehensive understanding of its antiarrhythmic mechanisms in the same preparations, amiodarone (50 µM) was employed as it would be in the clinical setting and applied to guinea pig papillary muscles impaled by microelectrodes, paced at different rates, and superfused with various concentrations of potassium ([K]_e). Amiodarone exerted complex actions, as follows: (1) The maximum rate of rise (V_max) of the fast action potential (i.e., [K]_e = 5.4–9.0mM) as well as that of the slow action potential (i.e., [K]_e = 15.0mM in the presence of 1.0µM isoproterenol) was suppressed in a rate-dependent manner. (2) Amiodarone exhibited a rate- and [K]_e-dependent increase in the ratio of effective refractory period vs action potential duration at 90% repolarization (ERP/APD₉₀), disclosing post-repolarization refractoriness. (3) Amiodarone had no effect on passive cable factors, such as threshold current and tissue resistance, during propagation. These versatile electrophysiological effects of amiodarone may contribute to its unique antiarrhythmic effects, as well as the low incidence of proarrhythmia with this drug.