Cajal间质细胞在胃肠运动中的作用

Cajal间质细胞(ICC)是肠神经系统中的一种与肠运动神经元及平滑肌密切相关的间质细胞，基于其形态学和组织学上与平滑肌和神经元的相互关系，ICC具有某些功能：起搏胃肠平滑肌运动并传导肌电信号，调节神经递质。ICC生物学特征是表达c-kit基因产物(编码酪氨酸激酶受体的原癌基因Kit)。平滑肌、肠神经系统和ICC共同形成复杂的胃肠运动控制系统；ICC缺失可能导致某些胃肠功能丧失，与一些胃肠疾病有关。     

Cajal间质细胞的功能与疾病

Cajal间质细胞是肠神经系统的一种特殊类型的神经细胞,在控制胃肠道运动中起着重要的作用。1893年,西班牙神经解剖学家Santiago Ramon y Cajal首先对此类细胞作了较详细的描述,此后人们即称之为Cajal间质细胞(interstitial cells of Cajal,ICC)。现基本明确,ICC在三个方面起作用:胃肠道平滑肌活动的起搏;推进电活动的传播;调节神经递质。现综述ICC的形态、结构、鉴别、发育、功能和与疾病的关系。 1 形态和超微结构在光镜下ICC的特征是核大,卵圆形,核周胞质少,2～5个长的突起,使ICC形状呈纺锤状或星状。ICC的超微结构特征因种属和在肠中位置不同而有差异。人类ICC的特征是发达的光面内质网,丰富的中间丝,没有肌球蛋白丝,无数的     

胃肠道Cajal间质细胞

Cajal间质细胞(interstitial cells of Cajal,ICC)是分布在消化道自主神经末梢与平滑肌细胞之间的一类特殊细胞.现已证实,ICC是胃肠道起搏细胞,具有产生、传播慢波的功能,并能传导肠神经系统至平滑肌的信号.2008年11月6日至9日在瑞士召开了第22届国际神经胃肠病学与胃肠动力学术研讨会,会议就ICC研究进行了广泛交流,本文综合会议报告内容,就胃肠道ICC研究进展作一综合复习.     

肠神经胶质细胞对肠上皮屏障的调节与功能紊乱疾病

肠神经胶质是肠神经系统的重要组成部分,其在胃肠道的黏膜中共同组成完整的神经调节体系.肠神经胶质细胞(enteric glial cells, EGCs)分布于肠壁的全层,并通过多条信号转导途径参与到了神经递质和神经调质对肠道功能的调节中.肠神经系统与肠道中的固有神经胶质细胞相互作用,参与上皮功能的调节.上皮细胞具有吸收和分泌的重要功能,同时参与到了肠道的屏障中.研究表明肠神经胶质不仅参与调控胃肠道的运动和上皮屏障功能,还参与形成肠神经元、肠内分泌细胞、免疫细胞和上皮细胞之间的细胞分子桥.本文主要对EGCs在肠道屏障和防御功能中的作用进展加以综述.     

钙敏感受体在肠神经系统中的表达

目的观察与探讨G-蛋白耦联受体(CASR)在豚鼠肠神经系统中的表达。方法以豚鼠为试验对象,先进行RT-PCR设计,然后采用Western blotting来检测豚鼠肠神经系统中CASR蛋白,并且应用间接法双重免疫荧光标记对肠神经系统整体、肠神经系统中的肌间神经丛黏膜下神经丛中的CASR分布及数量等进行测定,荧光标记物采用FITC和Cy3。结果无论是肠神经系统中的肌间神经丛还是黏膜下神经丛,不同的肠神经细胞中含有不同的神经元标记物,即均存在CASR。结论豚鼠肠神经系统存在钙敏感受体的表达,因此,关于CASR在肠神经系统中的相关研究具有重要的临床意义,可能为将来研究CASR在肠道神经系统中的功能及肠炎症中的作用奠定基础。     

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.     

Cajal间质细胞与肠炎性病变

Cajal间质细胞(interstitial cells of Cajal,ICC)是胃肠道运动的起搏细胞,它们参与起搏电流的传导和介导肠神经元与平滑肌细胞之间的神经信号。研究显示,ICC数目减少或缺乏的小肠和结肠将失去正常蠕动活性。证实ICC的病理学改变与胃肠运动障碍相关。炎症可引起胃肠运动障碍,ICC在其病理生理中的作用开始受到关注。对ICC在疾病状态下的作用进行详尽解释,还需要在生理和药理学方面进行更深入的研究。     

肠道炎症和恢复期Cajal间质细胞变化的相关机制

摘要炎症性肠病（IBD）患者常出现肠道动力紊乱，动力紊乱与肠道炎症密切相关。Cajal间质细胞（ICC）作为起搏细胞和肠道神经支配的调节者对控制胃肠道动力起关键作用。越来越多的证据显示在健康状态下或动力疾病中存在大量ICC的修复或再生。因此，明确ICC在肠道炎症中的病理生理机制，并阐明炎症恢复阶段促进ICC生长发育的因素具有重要意义。     

Cajal间质细胞与肠炎性病变

Cajal间质细胞(interstitial cells of Cajal，ICC)是胃肠道运动的起搏细胞，它们参与起搏电流的传导和介导肠神经元与平滑肌细胞之间的神经信号。研究显示，ICC数目减少或缺乏的小肠和结肠将失去正常蠕动活性。证实ICC的病理学改变与胃肠运动障碍相关。炎症可引起胃肠运动障碍，ICC在其病理生理中的作用开始受到关注。对ICC在疾病状态下的作用进行详尽解释，还需要在生理和药理学方面进行更深入的研究。     

肠黏膜分泌物调节肠易激综合征发病机制的研究进展

肠易激综合征(IBS)是一种以腹部不适或腹痛伴排便习惯改变为主要特征的功能性胃肠病。IBS的发病机制与胃肠动力学异常,内脏感觉异常、感染、精神心理因素等有关。其病理生理学机制尚不清楚,现认为脑肠轴神经免疫内分泌功能紊乱参与其中。近年来,研究发现肠黏膜的免疫炎性反应、内分泌功能紊乱以及神经营养因子分泌异常参与调节IBS脑肠轴功能紊乱并且导致肠黏膜异常分泌多种物质。此文主要阐述这些异常分泌的肠黏膜分泌物在IBS发病机制中的重要作用,并为IBS治疗提供一个广阔的前景。     

胃肠道神经-Cajal间质细胞-平滑肌网络研究进展

Cajal间质细胞是胃肠起搏细胞,并具有传导神经递质的作用.近年来的研究表明胃肠神经-ICC-平滑肌网络间存在密切的联系.此文就近期胃肠神经-ICC-平滑肌网络的研究进展作一综述.     

Autonome Neuropathie und mehr

In patients with diabetes almost all relevant regulatory systems and effector organs which are of importance for physiological functioning of gastrointestinal motility, secretion and sensitivity may be altered. Possible disturbances with negative effects on the gastrointestinal tract include autonomic neuropathy, enteric neuropathy with alterations of the myenteric and submucosal plexus, loss of interstitial cells of Cajal (ICC), altered secretion of insulin and other regulatory peptide hormones and diabetic myopathy of smooth muscles of the gastrointestinal canal. Moreover, almost all gastrointestinal functions are also impaired by hyperglycemia. In individual patients with gastrointestinal functional disturbances and corresponding complaints it is usually impossible to clarify the exact role of these mechanisms for the pathogenesis of symptoms; however, there is preliminary evidence that improved understanding may lead to new therapeutic options.     

Development of interstitial cells of Cajal and pacemaking in mice lacking enteric nerves.

BACKGROUND & AIMS: Development of interstitial cells of Cajal (ICC) requires signaling via Kit receptors. Kit is activated by stem cell factor (SCF), but the source of SCF in the bowel wall is unclear and controversy exists about whether enteric neurons express the SCF required for ICC development. METHODS: Glial cell line-derived neurotrophic factor (GDNF) knockout mice, which lack enteric neurons throughout most of the gut, were used to determine whether neurons are necessary for ICC development. ICC distributions were determined with Kit immunofluorescence, and function of ICC was determined by intracellular electrical recording. RESULTS: ICC were normally distributed throughout the gastrointestinal tracts of GDNF-/- mice. Intracellular recordings from aganglionic gastrointestinal muscles showed normal slow wave activity at birth in the stomach and small intestine. Slow waves developed normally in aganglionic segments of small bowel placed into organ culture at birth. Quantitative polymerase chain reaction showed similar expression of SCF in the muscles of animals with and without enteric neurons. Expression of SCF was demonstrated in isolated intestinal smooth muscle cells. CONCLUSIONS: These data suggest that enteric neurons are not required for the development of functional ICC. The circular smooth muscle layer, which develops before ICC, may be the source of SCF required for ICC development.     

The Importance of Interstitial Cells of Cajal in the Gastrointestinal Tract

Gastrointestinal (GI) motility function and its regulation is a complex process involving collaboration and communication of multiple cell types such as enteric neurons, interstitial cells of Cajal (ICC), and smooth muscle cells. Recent advances in GI research made a better understanding of ICC function and their role in the GI tract, and studies based on different types of techniques have shown that ICC, as an integral part of the GI neuromuscular apparatus, transduce inputs from enteric motor neurons, generate intrinsic electrical rhythmicity in phasic smooth muscles, and have a mechanical sensation ability. Absence or improper function of these cells has been linked to some GI tract disorders. This paper provides a general overview of ICC; their discovery, subtypes, function, locations in the GI tract, and some disorders associated with their loss or disease, and highlights some controversial issues with regard to the importance of ICC in the GI tract.     

胰岛素、干细胞因子和Cajal间质细胞在糖尿病胃轻瘫中的作用

糖尿病胃轻瘫是糖尿病的常见并发症，严重影响患者的生活质量和血糖控制。胃肠道Cajal间质细胞在维持胃肠功能中发挥重要作用，糖尿病智组织中存在Cajal间质细胞数量和结构的异常改变，从而影响胃动力。胰岛素、干细胞因子对糖尿病胃肠道Cajal间质细胞的病变具有重要调控作用。本文就胰岛素、干细胞因子和Cajal间质细胞在糖尿病胃轻瘫中的作用作一综述。     

肠神经系统退行性变的研究进展

肠神经系统(enteric nervous system,ENS)可独立调节胃肠道感觉、分泌和运动功能,ENS退行性变可导致胃肠道功能的异常,引起一系列的临床症状,其与胃肠动力性疾病和功能性胃肠病的发病有关。本文就导致ENS退行性变的原因、肠神经元退行性变引起的功能异常及其与临床症状的关联性、可能的治疗靶点等方面的研究进展作一概述。     

Role of biological rhythms in gastrointestinal health and disease

The molecular basis for biological rhythms is formed by clock genes. Clock genes are functional in the liver, within gastrointestinal epithelial cells and neurons of the enteric nervous system. These observations suggest a possible role for clock genes in various circadian functions of the liver and the gastrointestinal tract through the modulation of organ specific clock-controlled genes. Consequently, disruptions in circadian rhythmicity may lead to adverse health consequences. This review will focus on the current understanding of the role of circadian rhythms in the pathogenesis of gastrointestinal- and hepatic disease such as obesity, non-alcoholic fatty liver disease, alcoholic fatty liver disease and alterations in colonic motility.     

Interstitial cells of Cajal mediate inhibitory neurotransmission in the stomach.

The structural relationships between interstitial cells of Cajal (ICC), varicose nerve fibers, and smooth muscle cells in the gastrointestinal tract have led to the suggestion that ICC may be involved in or mediate enteric neurotransmission. We characterized the distribution of ICC in the murine stomach and found two distinct classes on the basis of morphology and immunoreactivity to antibodies against c-Kit receptors. ICC with multiple processes formed a network in the myenteric plexus region from corpus to pylorus. Spindle-shaped ICC were found within the circular and longitudinal muscle layers (IC-IM) throughout the stomach. The density of these cells was greatest in the proximal stomach. IC-IM ran along nerve fibers and were closely associated with nerve terminals and adjacent smooth muscle cells. IC-IM failed to develop in mice with mutations in c-kit. Therefore, we used W/W(V) mutants to test whether IC-IM mediate neural inputs in muscles of the gastric fundus. The distribution of inhibitory nerves in the stomachs of c-kit mutants was normal, but NO-dependent inhibitory neuro-regulation was greatly reduced. Smooth muscle tissues of W/W(V) mutants relaxed in response to exogenous sodium nitroprusside, but the membrane potential effects of sodium nitroprusside were attenuated. These data suggest that IC-IM play a critical serial role in NO-dependent neurotransmission: the cellular mechanism(s) responsible for transducing NO into electrical responses may be expressed in IC-IM. Loss of these cells causes loss of electrical responsiveness and greatly reduces responses to nitrergic nerve stimulation.     

Diagnostik und Therapie gastrointestinaler Funktionsstörungen bei Diabetes mellitus

Gastrointestinal functional disturbances frequently cause abdominal symptoms in patients with diabetes mellitus and have been shown to impair the quality of life. Autonomic neuropathy is an important pathomechanism but other disturbances affecting the enteric nervous system, interstitial cells of Cajal (ICC), smooth muscle cells, release of insulin and other regulatory peptide hormones and glucose homeostasis also contribute to the pathogenesis. Diagnostic procedures should start with exclusion of infectious and structural diseases by laboratory investigations, endoscopy, abdominal sonography and/or radiological methods. If the diagnosis remains unclear individual parameters decide whether a therapeutic trial can be started or whether functional diagnostic procedures are needed for further clarification. Optimization of blood glucose control is generally of importance but frequently difficult to achieve due to interactions between gastrointestinal dysfunction and blood glucose control. Apart from this, symptom-oriented therapy is usually performed as established for patients without diabetes. Moreover, diabetes-associated functional disturbances, particularly those affecting the proximal gastrointestinal tract, may cause few symptoms but may still impair blood glucose and therefore need therapy. In this article the diabetes-associated diseases dysphagia, reflux disease, gastropathy, exocrine pancreatic insufficiency, gallbladder dysfunction, diarrhea, constipation and stool incontinence are discussed with respect to the diagnostic procedures and therapy     

Cajal间质细胞与糖尿病胃轻瘫的关系

Cajal间质细胞（ICC）是胃肠道中与肠神经细胞和平滑肌密切相关的间质细胞,网络状分布于整个胃肠组织,对胃肠慢波的产生及胃肠动力的维持起关键作用。研究表明,糖尿病胃轻瘫（DGP）患者及其动物模型均存在ICC数目明显减少、结构破坏、且与神经末梢及平滑肌之间的连接减少。因此,ICC的异常可能是DGP的重要原因之一。本文就ICC与DGP的研究现状进行探讨。