钙离子在大鼠结肠平滑肌运动中作用机制的研究

目的 应用束缚应激大鼠实验模型,研究离体结肠平滑肌的收缩运动及其影响因素,探讨鸟苷素在结肠运动中的作用。方法 建立束缚应激大鼠动物模型,制备离体结肠平滑肌环行肌及纵行肌肌条,应用张力换能器,测定其肌张力。应用放射配基法测定结肠组织及血浆中鸟苷素含量。结果 束缚应激刺激可诱发大鼠排便增加,该动物模型是较好的模拟人ＩＢＳ的实验动物模型。束缚应激大鼠离体结肠平滑肌的张力升高,对Ｋ＾＋、Ｃａ＾２＋、乙酰胆     

银杏叶提取物对豚鼠结肠平滑肌细胞的直接作用

目的 :探讨银杏叶提取物 (ExtractofGinkgobiloba,EGb)对豚鼠游离结肠平滑肌细胞的直接作用机制。方法 :用含 1g/LⅠ型胶原酶及 0 .1g/L大豆胰蛋白酶抑制剂的消化液 ,消化获得游离的豚鼠结肠平滑肌细胞 ,将不同浓度EGb加入细胞悬液中 ,用显微镜测微尺随机观察 50个细胞长轴变化情况 ,计算用药前后细胞平均长度。如果 :EGb对结肠平滑肌细胞具有舒张作用 ,在 0 .1 1～ 3 .5g/L浓度范围内 ,EGb对结肠平滑肌细胞的作用呈剂量 -效应关系 ,最大反映浓度为 1 .75g/L ,其舒张效应为 1 2 .79% (P <0 .0 5)。EGb预先孵育 1min ,可抑制乙酰胆碱 (ACh)效应的 44 .1 3 % (P <0 .0 1 )。腺苷酸环化酶激动剂Forskolin可增强EGb的舒张效应 ,与单独应用EGb组相比较 ,舒张百分数增加 8.87% (P <0 .0 5)。结论 :EGb对豚鼠游离结肠平滑肌细胞具有直接作用 ,这种作用可能与cAMP信号传导通路相关     

肠易激综合征患者结肠黏膜P物质、血管活性肠肽和肥大细胞的变化

背景：肠易激综合征（IBS）的发病机制尚不明确。目的：探讨IBS患者结肠黏膜P物质（SP）、血管活性肠肽（VIP）、肥大细胞（MC）的变化及其在IBS中的可能作用。方法：20例腹泻型IBS患者、22例便秘型IBS患者和18名正常对照者纳入本研究．取回盲部、乙状结肠黏膜行SP、VIP免疫组化染色和MC计数。结果：IBS患者回盲部、乙状结肠黏膜SP、VIP免疫阳性神经纤维较正常对照组增多、增粗，阳性增强（P〈0．05）。IBS患者乙状结肠黏膜SP、VIP免疫阳性神经纤维与回盲部相比无显著差异。IBS患者回盲部黏膜MC计数较正常对照组显著增高（P〈0．01），乙状结肠黏膜MC计数与正常对照组相比无显著差异。IBS患者乙状结肠黏膜MC计数与正常对照组相比，显著低于回盲部（P〈0．01）。结论：SP、VIP和MC在IBS的发病中起有一定作用。     

温针灸对慢传输型便秘大鼠结肠P物质、血管活性肠肽表达的影响

目的 探讨温针灸对慢传输型便秘(STC)大鼠肠道传输功能及结肠P物质(SP)、血管活性肠肽(VIP)阳性表达的影响.方法 选用SD大鼠100只,随机取10只为正常组,其余90只造成STC大鼠模型,并随机分为模型组、针刺组和温针组.分别测定大鼠肠道传输功能及结肠SP、VIP阳性表达面积.结果 针刺组、温针组可明显缩短大鼠首粒黑便排出时间(P＜0.01),且温针灸效果优于针刺组(P＜0.05).STC大鼠结肠SP、VIP阳性表达较正常组明显降低(P＜0.01);针刺和温针灸均能明显提高结肠SP、VIP阳性表达面积(P＜0.01);且温针灸在提高结肠SP阳性表达面积上效果优于单纯针刺(P＜0.01).结论 针灸治疗STC有效,其机制与提高结肠SP、VIP阳性表达有关;温针灸效果更好.     

哮喘患者血浆P物质和血管活性肠肽含量变化及其临床意义

用放射免疫分析法测定不同信群血浆ＳＰ，ＶＩＰ浓度及其对治疗的反应，结果：（１）缓解期血浆ＳＰ浓度升高，ＶＩＰ浓度下降，与对照组比较有显著性差异；（２）发作期组治疗前血浆ＳＰ，ＶＩＰ浓度变化较缓解期及正常组比较有显著性差异，（３）发作期组治疗后ＳＰ，ＶＩＰ浓度与治疗前比较有显著性差异，与缓解期组比较无显著性差异，结论：哮喘病人气道粘膜病理学改变致血浆ＳＰ浓度升高，ＶＩＰ浓度下降，与临床症状加重同步，     

实验性脾虚证结肠动力及胃肠肽和一氧化氮合酶改变

近年对脾虚证胃肠道电一机械活动的研究多集中于上消化道[1-5],对下消化道的研究尚不多见[6-8].     

参苓白术散对腹泻小鼠胃肠运动功能的影响及机制探讨

目的 通过对腹泻小鼠胃肠运动和腹泻大鼠结肠中胃肠肽蛋白表达影响的研究,探讨参苓白术散对腹泻的作用及其机制.方法 采用番泻叶泻下法复制模型,观察小鼠的排便次数、腹泻率、稀便级、稀便率、腹泻指数;用碳末推进法观测小肠碳末推进率的变化;免疫组织化学法检测结肠中P物质(SP)、血管活性肠肽(VIP)蛋白表达,观察参苓白术散对其干预作用.结果 经番泻叶泻下法复制模型后,小鼠的排便次数、腹泻率、稀便级、稀便率、腹泻指数升高;大鼠结肠中SP和VIP蛋白表达升高.参苓白术散治疗后,腹泻小鼠排便次数、腹泻率、稀便级、稀便率、腹泻指数降低,小肠推进被抑制;大鼠结肠中SP、VIP蛋白表达降低.结论 参苓白术散可以明显抑制胃肠运动,降低SP、VIP蛋白表达可能是其作用机制之一.     

大黄对大鼠胃运动的影响及机制

目的 :探讨大黄对大鼠胃排空运动的影响及其机制 ,为临床应用大黄提供理论依据。方法 :32只 Wistar大鼠随机分为大黄组及对照组 ,分别给大鼠灌服大黄水提液或蒸馏水 1、6 h后 ,以葡聚糖蓝 - 2 0 0 0为胃肠内标记物观察大鼠胃排空的变化 ,同时用免疫组化染色观察胃窦肌间神经丛 P物质 (SP)、血管活性肠肽 (VIP)的分布变化。结果 :灌服大黄水提液后 ,大鼠胃排空运动显著抑制 (P <0 .0 5或 <0 .0 1) ,胃窦肌间神经丛 SP的分布明显减少 (P<0 .0 5或 <0 .0 1) ,VIP分布明显增加 (P <0 .0 5或 <0 .0 1)。结论 :大黄对大鼠胃运动有明显的抑制作用 ,其机制可能与胃窦肌间神经丛 SP的分布减少及 VIP的分布增加有关     

白细胞介素6对豚鼠离体近端结肠平滑肌收缩的影响

目的:研究白细胞介素6(IL-6)对豚鼠近端结肠平滑肌的影响及其机制.方法:观察IL-6对结肠收缩的影响;用河豚毒素(TTX)阻断肠神经后观察不同浓度IL-6对结肠平滑肌收缩的影响;损伤Cajal间质细胞(ICC)后观察IL-6对结肠平滑肌收缩的影响.结果:在带有ICC的近端结肠纵行肌加入IL-6后,结肠平滑肌的收缩振幅增加和频率加快,呈浓度依赖性:加入TTX后,收缩的幅度和频率,同拮抗前相比分别降低和减慢(0.206±0.027 g vs 0.300±0.039 g;9.770±1.711 s vs 8.483±1.113 s:P<0.01,P<0.05):TTX阻断后加入IL-6(80μg/L),振幅增加和频率加快(P<0.01,P<0.05):破坏结肠ICC,收缩幅度和频率分别与损伤ICC后加入IL-6无显著性差异(80μg/L),而与正常结肠收缩振幅和频率有显著性差异(P<0.01).结论:IL-6对豚鼠近端结肠平滑肌的收缩活动有兴奋作用,其兴奋效应主要是通过肠神经元介导.ICC是IL-6对平滑肌兴奋途径的一个不可缺少的中间环节.     

慢性便秘患者直肠 P物质和血管活性肠肽含量的变化

慢性特发性便秘 (ＣＩＣ)是一种病因未明的常见临床症状 ,结、直肠运动功能紊乱与其发病密切相关。胃肠运动主要受肠神经系统调节 ,发挥调节作用的是神经递质。我们采用放免法测定ＣＩＣ患者直肠活检组织中Ｐ物质 (ＳＰ)和血管活性肠肽 (ＶＩＰ)含量变化 ,旨在探讨肠神经递质在ＣＩＣ发病中的作用。1 对象 :ＣＩＣ患者 2 4例 ,男 9例 ,女 15例 ,年龄 30～ 6 2岁 ,平均 (4 0 2± 9 8)岁。病程为 2～ 2 5年。正常健康者14例 ,男 5例 ,女 9例 ,年龄 2 6～ 5 6岁 ,平均 (38 7± 9 6 )岁。2 方法 :通过结肠镜在所有受试者距肛门齿状线上 5ｃｍ…     

中药促结肠动力作用的筛选研究

目的 :探讨中药的促结肠动力作用 ,以筛选出具有开发价值的促结肠动力药物。方法 :制备大鼠结肠纵肌和横肌肌条 ,以 0 .85 %氯化钠溶液和乙酰胆碱为对照 ,观察元胡、香附、白芍、生白术、蒲公英、小茴香、大腹皮、大黄、莱菔子、厚朴、槟榔 11味中药对离体结肠肌收缩活性的效应。结果 :该 11味中药对肌条均有不同程度的兴奋效应 (P <0 .0 5 ) ,其中 ,槟榔、莱菔子、小茴香、生白术对横肌及纵肌均有显著性的兴奋作用 ,蒲公英对平滑肌肌条的兴奋作用以横肌较为显著 ,白芍作用较弱。结论 :槟榔、小茴香、蒲公英、莱菔子、生白术具有较强的促结肠动力作用 ,可以进一步研究开发。     

血管平滑肌细胞凋亡机制的研究进展

血管平滑肌细胞凋亡与很多心血管疾病的发生、发展密切相关,目前已经成为心血管疾病防治研究的热点。现对血管平滑肌细胞凋亡机制的研究现状进行了较为深入的探讨,从其诱导因素以及基因调控机制等角度综述了近年来国内外在这方面的研究进展。     

Pharmacological Study of Oyster Mushroom (<Emphasis Type="Italic">Pleurotus Ostreatus</Emphasis>) Extract on Isolated Guinea Pig Trachea Smooth Muscle

Mushroom farm workers suffer from respiratory symptoms during the farming of mushrooms. The objective of this study was to analyze the effects of oyster mushroom (Pleurotus ostreatus) extract (OME) on isolated guinea pig tracheal smooth muscle in vitro. Isolated guinea pig tracheal tissue from 27 nonsensitized guinea pigs were studied. The OME was obtained from indoor mushroom growing fields and prepared as a 1:10 w/v aqueous solution. Dose-related contractions of nonsensitized guinea pig trachea were demonstrated using these extracts. The OME contained significant quantities of bacterial components (eg., endotoxin: 43,072.92 EU/mg). Parallel, pharmacological studies were performed by pre-treating the tissues with mediator-modifying agents including atropine, indomethacin, pyrilamine, BPB, acivicin, NDGA, captopril, TMB8 and capsaicin. Atropine consistently and strikingly reduced the contractile effects of this extract. These observations suggest an interaction of the OME with parasympathetic nerves or more directly with muscarinic receptors. Pretreatment with TMB8 (inhibitor of intracellular calcium mobilization) also significantly blocked the constrictor effect of OME, indicating a role of calcium mobilization in the constricting effect of OME. Inhibition of contraction by blocking of other mediators was less effective and varied depending on the drug. We conclude that OME causes a dose-related airway smooth muscle constriction by nonimmunological mechanisms involving a variety of airway mediators and possibly cholinergic receptors. This effect is not dependent on pre-sensitization of the guinea pigs.     

Short-Chain Fatty Acids Induce Cytoskeletal and Extracellular Protein Modifications Associated with Modulation of Proliferation on Primary Culture of Rat Intestinal Smooth Muscle Cells

Short-chain fatty acids are the main end products of bacterial fermentation of carbohydrates. Their role on the metabolism and biology of colonocytes is now well characterized. However, the functional consequences of their presence on intestinal smooth muscle cells remain poorly studied. We aimed to assess the effect of different short-chain fatty acids on ileal and colonic smooth muscle cells in primary culture and on A7R5 line. Butyrate (above 0.1 mM) inhibited A7R5 cell proliferation, while at low concentration (0.05 to 0.5 mM) butyrate significantly stimulated the proliferation of ileal and colonic myocytes in primary culture. An inhibition was observed at higher concentrations. Collagenous and noncollagenous protein synthesis was stimulated by butyrate. Moreover, butyrate stimulated actin and myosin expression. Thus, butyrate, which is produced by dietary fiber fermentation, may affect intestinal muscles by directly acting at the molecular level on myocytes.     

Frictional Behavior of Individual Vascular Smooth Muscle Cells Assessed By Lateral Force Microscopy

With the advancement of the field of biotribology, considerable interest has arisen in the study of cell and tissue frictional properties. From the perspective of medical device development, the frictional properties between a rigid surface and underlying cells and tissues are of a particular clinical interest. As with many bearing surfaces, it is likely that contact asperities exist at the size scale of single cells and below. Thus, a technique to measure cellular frictional properties directly would be beneficial from both a clinical and a basic science perspective. In the current study, an atomic force microscope (AFM) with a 5 μm diameter borosilicate spherical probe simulating endovascular metallic stent asperities was used to characterize the surface frictional properties of vascular smooth muscle cells (VSMCs) in contact with a metallic endovascular stent. Various treatments were used to alter cell structure, in order to better understand the cellular components and mechanisms responsible for governing frictional properties. The frictional coefficient of the probe on VSMCs was found to be approximately 0.06. This frictional coefficient was significantly affected by cellular crosslinking and cytoskeletal depolymerization agents. These results demonstrate that AFM-based lateral force microscopy is a valuable technique to assess the friction properties of individual single cells on the micro-scale.     

27nt-miRNA通过靶向哺乳动物雷帕霉素靶蛋白调控血管平滑肌细胞凋亡及其分子机制研究

目的:探讨来源于一氧化氮合酶基因第四内含子的27碱基重复序列微小RNA(27nt-miRNA)对哺乳动物雷帕霉素靶蛋白(mTOR)介导的主动脉血管平滑肌细胞(VSMC)凋亡调控作用及潜在分子机制。方法:将大鼠主动脉VSMC分为空白对照组、雷帕霉素组、27nt-miRNA组、27nt-miRNA反义序列(anti-27ntmiRNA)组、阴性对照组。27nt-miRNA组:转染27nt-miRNA正义链慢病毒载体;anti-27nt-miRNA组:转染27ntmiRNA反义链慢病毒载体;阴性对照组:转染随机阴性序列慢病毒载体。除空白对照组外,雷帕霉素组与各转染组细胞给予100 ng/ml雷帕霉素诱导培养2 h诱导凋亡。荧光定量逆转录PCR(qRT-PCR)验证27nt-miRNA慢病毒稳转细胞株构建情况;CCK-8法、流式细胞术、qRT-PCR法与蛋白免疫印迹(Western blot)法分别检测各组细胞增殖能力、细胞凋亡率与周期分布以及mTOR、磷酸化-mTOR(p-mTOR)、B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)和半胱氨酸天冬氨酸蛋白酶-3(caspase-3)的信使RNA(mRNA)和(或)蛋白表达水平。结果:慢病毒转染VSMC后,27nt-miRNA稳转细胞株构建成功,雷帕霉素可抑制VSMC的mTOR mRNA与p-mTOR蛋白表达水平。与阴性对照组相比,27nt-miRNA组细胞的活力与增殖能力显著增强,且细胞凋亡率显著降低(P均<0.05),细胞周期G1期向S期分裂进程阻滞减弱(P<0.05);Bax和caspase-3蛋白表达量显著减少,Bcl-2蛋白表达量显著增加(P均<0.05);mTOR基因转录水平与p-mTOR蛋白表达水平均下降(P<0.05)。结论:27nt-miRNA通过负调控m TOR基因转录水平与蛋白磷酸化水平抑制VSMC凋亡,其机制可能与上调Bcl-2蛋白表达,下调Bax和caspase-3蛋白表达有关。     

Effect of Dexamethasone on Bovine Airway Smooth Muscle Cell Proliferation

Airway smooth muscle proliferation is a key component of airway wall remodelling that occurs as a consequence of inflammation in asthma. Studies were conducted to examine the effect of dexamethasone on airway smooth muscle cell (ASMC) proliferation in vitro. Dexamethasone (25-250 nM) significantly inhibited DNA synthesis and cell division induced by β-hexosaminidase A (Hex A, 50 nM) in bovine ASMC. The inhibitory effect of dexamethasone on DNA synthesis was variable depending on the growth factors: significant effect was observed on Hex A and insulin; no significant effect was observed on epidermal growth factor and fetal bovine serum.     

Pharmacologic Effects of Grain Weevil Extract on Isolated Guinea Pig Tracheal Smooth Muscle

The grain weevil, an insect (pest) that infects grain, is a frequent contaminant of processed wheat, and its presence may contribute to respiratory abnormalities in grain workers. We studied the in vitro effects of an extract of grain weevil (GWE) on airway smooth muscle. Pharmacologic studies included in vitro challenge of guinea pig trachea with GWE, in parallel organ baths, pretreated with mediator-modifying agents or a control solution. Dose-related contractions of nonsensitized guinea pig trachea (GPT) were demonstrated using this extract. Pharmacologic studies were performed by pretreating guinea pig tracheal tissue with drugs known to modulate smooth muscle contraction: atropine, indomethacin, pyrilamine, acivicin, NDGA, BPB, TMB8, captopril, and capsaicin. Atropine, pyrilamine, BPB, and capsaicin significantly reduced the contractile effects of the extract at most of the challenge doses (p < 0.01 or p < 0.05). Inhibition of GWE-induced contraction by blocking of other mediators was less complete. We suggest that GWE causes dose-related airway smooth muscle constriction of the GPT by nonimmunologic mechanisms involving a variety of airway mediators and possibly cholinergic receptors.     

葛根素诱导血管平滑肌细胞凋亡的实验研究

目的：观察葛根素促进人脐动脉血管平滑肌细胞凋亡的作用，探讨葛根素抑制平滑肌细胞增殖的机制。方法：分离培养人脐动脉平滑肌细胞，不同浓度葛根素与细胞孵育，TUNEL检测葛根素诱导细胞凋亡，rt-PCR实验检测促凋亡基因Bax和抗凋亡基因Bcl-XL。结果：随着葛根素浓度升高，细胞生长受抑制，TUNEL阳性细胞显著增加。rt-PCR实验发现促凋亡基因Bax随药物浓度和作用时间的增加而上升，而且Bax、Bcl-XL基因表达比例有一定升高。结论：葛根素通过调节经典的Bax、Bcl-XL通路对血管平滑肌细胞凋亡有一定诱导作用。