Presence of c-kit positive cells in fetal and adult bovine forestomachs

The interstitial cells of Cajal (ICC) have been reported to regulate gastrointestinal motility. We investigated the distribution and the morphological and morphometric characteristics of the immunohistochemical reaction against c-kit in the forestomachs of fetal, newborn and adult cows. The anti-c-kit reaction revealed different populations of ICC among age groups and organs. ICC were more numerous and smaller in fetuses. Larger ICC were identified in newborns, except for those in the rumen. During the earliest stages of development, ICC were abundant in the inner layer of the muscularis and were consistently associated with this layer. In all samples, ICC were found in the outer layer of the tunica muscularis. ICC were found between the two muscle layers in the omasum at all ages; however, they were identified only in the rumen of the adult. Our study demonstrated that ICC are present in the forestomach of bovines.     

干细胞因子及其受体在红系分化中的作用

干细胞因子作为一种多能细胞因子,在临床上有较好的应用前景。随着CD34^ 细胞分离培养技术的完善,干细胞因子及其受体在红系增殖、分化中的重要作用正逐渐被发现并阐述清楚,对临床上相关疾病的治疗有重要的指导意义。本介绍了干系胞因子及其配体抑制红系祖细胞凋亡和促进红系祖细胞增殖和分化的功能,以及在临床上的应用前景。     

CD117/c-kit positive interstitial (Cajal-like) cells in human pancreas

We provide evidence that interstitial Cajal-like cells, previously described in human pancreas - pICC ( J Cel Mol Med , 9: 169, 2005), are positive for c-kit irrespective of immunohistochemical procedures used. Various sample types (fresh cryosections or formalin-fixed, paraffin-embedded specimens), various slide pretreatments (with or without heat-induced epitope retrieval) or different antibodies used (Dako polyclonal or Santa Cruz monoclonal), all showed CD117-positive pICC.     

内脏平滑肌Cajal间质细胞起搏功能(英文)

胃肠道的大部分区域都存在着一种特殊的间质细胞——Cajal间质细胞(interstitial cells of Cajal,ICCs)。尽管在100多年前它们的存在就已被发现,但是直到最近几十年的研究才逐渐揭示了它们的功能。在胃肠道,ICCs被认为是平滑肌自发性节律性电活动,即"基本电节律"(又称"慢波")的起搏细胞,并介导神经至平滑肌的神经信号传递活动。除胃肠道外,ICC样细胞同样存在于其它内脏平滑肌,如泌尿、生殖系统以及血管平滑肌等。本文仅就这些内脏平滑肌ICCs的功能做一简单综述。     

Generation of functional gut-like organ from mouse induced pluripotent stem cells

Induced pluripotent stem (iPS) cells have the pluripotency to differentiate into broad spectrum derivatives of all three embryonic germ layers. However, the in vitro organ differentiation potential of iPS cells to organize a complex and functional “organ” has not yet been demonstrated. Here, we demonstrate that mouse iPS cells have the ability to organize a gut-like organ with motor function in vitro by a hanging drop culture system. This “induced gut (iGut)” exhibited spontaneous contraction and highly coordinated peristalsis accompanied by a transportation of contents. Ultrastructural analysis identified that the iGut had large lumens surrounded by three distinct layers (epithelium, connective tissue and musculature). Immunoreactivity for c-Kit, a marker of interstitial cells of Cajal (ICCs, enteric pacemaker cells), was observed in the wall of the lumen and formed a distinct and dense network. The neurofilament immunoreactivity was identified to form large ganglion-like structures and dense neuronal networks. The iGut was composed of all the enteric components of three germ layers: epithelial cells (endoderm), smooth muscle cells (mesoderm), ICCs (mesoderm), and enteric neurons (ectoderm). This is the first report to demonstrate the in vitro differentiation potential of iPS cells into particular types of functional “organs.” This work not only contributes to understanding the mechanisms of incurable gut disease through disease-specific iPS cells, but also facilitates the clinical application of patient-specific iPS cells for novel therapeutic strategies such as patient-specific “organ” regenerative medicine in the future.     

Platelet-derived growth factor receptor-α cells in mouse urinary bladder: a new class of interstitial cells

Specific classes of interstitial cells exist in visceral organs and have been implicated in several physiological functions including pacemaking and mediators in neurotransmission. In the bladder, Kit(+) interstitial cells have been reported to exist and have been suggested to be neuromodulators. More recently a second interstitial cell, which is identified using antibodies against platelet-derived growth factor receptor-α (PDGFR-α) has been described in the gastrointestinal (GI) tract and has been implicated in enteric motor neurotransmission. In this study, we examined the distribution of PDGFR-α(+) cells in the murine urinary bladder and the relation that these cells may have with nerve fibres and smooth muscle cells. Platelet-derived growth factor receptor-α(+) cells had a spindle shape or stellate morphology and often possessed multiple processes that contacted one another forming a loose network. These cells were distributed throughout the bladder wall, being present in the lamina propria as well as throughout the muscularis of the detrusor. These cells surrounded and were located between smooth muscle bundles and often came into close morphological association with intramural nerve fibres. These data describe a new class of interstitial cells that express a specific receptor within the bladder wall and provide morphological evidence for a possible neuromodulatory role in bladder function.     

胚胎小肠Cajal细胞的发育研究

目的研究人胚胎小肠cajal细胞的发育变化规律。方法采用全层铺片结合切片的免疫细胞化学技术。结果Cajal细胞呈酪氨酸激酶受体(Kit)和波形蛋白(vinlentin)免疫反应阳性。在胚胎发育早期,cajal细胞较少,为单层,稀疏分布于肌间神经丛周围,细胞为梭形,可见两个短而小的突起,未见分支;随着胎龄的增加,Cajal细胞数量增多,胞体增大,突起伸长,并出现分支。此时,肌间神经丛周围的Cajal细胞出现两层,其长轴彼此垂直,分别平行于环行肌和纵行肌。与此同时环行肌层内亦可见少许Cajal细胞;出生前,肌间神经丛部位的Cajal细胞接近成熟,两层细胞的突起进一步增多、伸长,彼此间形成与成人相似的完整的细胞网络。此时深肌丛附近亦可见少量Cajal细胞。结论人的小肠Cajal细胞发育有一定的时间顺序,即肌间神经丛周围最先出现,肌内次之,深肌丛较晚,出生前肌间神经丛周围的Cajal细胞已经接近成熟。这种发育演变若发生异常,可能导致某些胃肠动力障碍性疾病。     

模拟失重对大鼠血清胃泌素、胃动素和胃窦Cajal间质细胞的影响

目的：研究尾悬吊模拟失重环境对大鼠血清胃泌素（GAS）、胃动素（MTL）和胃窦Cajal间质细胞（ICC）的影响。方法：健康雄性Wistar大鼠64只随机分为8组（rt=8）,按模拟失重时相分别设为6h、12h、1d、2d、3d、5d、7d和0h（地面对照组）组,采用尾悬吊法建立模拟失重动物模型。应用放免法测定血清GAS、MTL浓度,免疫组化和RT—PCR技术检测各组大鼠胃窦组织中c—kit蛋白和mRNA表达情况。结果：尾悬吊6、12h阶段,血清GAS浓度明显升高,与对照组比较差异有统计学意义（P〈0．05）;随尾悬吊时相延长,血清GAS含量呈逐渐下降趋势,与正常对照组水平相近。尾悬吊各组大鼠血清MTL浓度均升高,12h以后各组MTL浓度值与对照组比较,差异有统计学意义（P〈0．05）。免疫组化结果显示,c—kit蛋白阳性表达为棕褐色,主要分布在ICC胞体和突起,正常对照组大鼠胃窦肌层ICC（ICC—MY）呈连续性浓染,肌层内ICC（ICC—IM）亦明晰可见;6h-5d的尾悬吊过程中,大鼠胃窦ICC—MY连续性出现中断现象且逐渐明显,染色逐渐减弱,ICC—IM染色减弱的同时c—kit阳性ICC也明显减少;7d组胃窦组织中c—kit蛋白表达有所恢复。模拟失重各组及对照组大鼠胃窦组织中均有c—kitmRNA表达,尾悬吊6、12h组的c—kitmRNA表达明显下降,与对照组比较,差异有统计学意义（P〈0．05）,1～3d组逐渐恢复,5d组又出现明显下降（P〈0．05）,7d组c—kitmRNA表达值明显复升。结论：尾悬吊模拟失重对大鼠血清GAS、MTL和胃窦Cajal间质细胞c—kit蛋白及mRNA表达造成明显影响,可能导致胃动力障碍。     

In vitro enhanced differentiation of neural networks in ES gut-like organ from mouse ES cells by a 5-HT4-receptor activation

Using an embryoid body (EB) culture system, we developed a functional organ-like cluster, a “gut”, from mouse embryonic stem (ES) cells (ES gut). Each ES gut exhibited various types of spontaneous movements. In these spontaneously contracting ES guts, dense distributions of interstitial cells of Cajal (ICC) (c-kit, a transmembrane receptor that has tyrosine kinase activity, positive cells; gut pacemaker cells) and smooth muscle cells were discernibly identified, but enteric neural networks were not identified. In the present study, we succeeded in forming dense enteric neural networks by a 5-HT₄-receptor (SR4) agonist, mosapride citrate (1–10 μM) added only during EB formation. Addition of an SR4-antagonist, GR113808 (10 μM) abolished the SR4-agonist-induced formation of enteric neural networks. The SR4-agonist (1 μM) up-regulated the expression of mRNA of SR4 and the SR4-antagonist abolished this upregulation. 5-HT per se exerted similar effects to those of SR4-agonist, though less potent. These results suggest SR4-agonist differentiated enteric neural networks, mediated via activation of SR4 in the ES gut.     

Inhibition of gut pacemaker cell formation from mouse ES cells by the c-kit inhibitor

Using an embryoid body (EB) culture system, we developed a functional organ-like cluster, a "gut", from mouse embryonic stem (ES) cells (ES gut). Each ES gut exhibited various types of spontaneous movements. In these spontaneously contracting ES guts, dense distributions of interstitial cells of Cajal (ICC) (c-kit, a transmembrane receptor that has tyrosine kinase activity, positive cells; gut pacemaker cells) and smooth muscle cells were discernibly identified. By adding Glivec 10(-5)M, a tyrosine kinase receptor c-kit inhibitor, only during EB formation, we for the first time succeeded in suppressing in vitro formation of ICC in the ES gut. The ES gut without ICC did not exhibit any movements. However, it appeared that Glivec 10(-6)-10(-7)M rather increased number of ES guts with spontaneous movements associated with increase of intracellular Ca(2+) concentration ([Ca(2+)](i)). These results suggest ICC is critical for in vitro formation of ES guts with spontaneous movements.     

Inherent rhythmcity and interstitial cells of Cajal in a frog vein

Interstitial cells of Cajal are responsible for rhythmic contractions of the musculature of the gastrointestinal tract and blood vessels. The existence of these cells and spontaneous rhythmicity were noticed in amphibian vein and the findings are reported in this paper. The postcaval vein was identified in the frog, Rana tigrina and was perfused with amphibian Ringer solution after isolation. Contractile activity was recorded through a tension transducer connected to a polygraph. The isolated postcaval vein showed spontaneous rhythmic activity. Addition of cold Ringer solution decreased, while warm Ringer increased, the rate of contraction. Adrenaline caused inhibition of rhythmic activity at a dosage that increased the rate of isolated sinus venosus. Sections of the postcaval vein, when stained supravitally with methylene blue, showed the presence of interstitial cells of Cajal. Photic stimulation of the vein in the presence of methylene blue led to a significant decrease in the rate of spontaneous beating of the vein. These findings indicate that the postcaval vein of frog is capable of inherent rhythmcity, which is dependent on the interstitial cells of Cajal but is independent of the sinus venosus.     

Carbachol regulates pacemaker activities in cultured interstitial cells of Cajal from the mouse small intestine

We studied the effect of carbachol on pacemaker currents in cultured interstitial cells of Cajal (ICC) from the mouse small intestine by muscarinic stimulation using a whole cell patch clamp technique and Ca²⁺-imaging. ICC generated periodic pacemaker potentials in the current-clamp mode and generated spontaneous inward pacemaker currents at a holding potential of–70 mV. Exposure to carbachol depolarized the membrane and produced tonic inward pacemaker currents with a decrease in the frequency and amplitude of the pacemaker currents. The effects of carbachol were blocked by 1-dimethyl-4-diphenylacetoxypiperidinium, a muscarinic M₃ receptor antagonist, but not by methotramine, a muscarinic M₂ receptor antagonist. Intracellular GDP-β-S suppressed the carbachol-induced effects. Carbachol-induced effects were blocked by external Na⁺-free solution and by flufenamic acid, a non-selective cation channel blocker, and in the presence of thapsigargin, a Ca²⁺-ATPase inhibitor in the endoplasmic reticulum. However, carbachol still produced tonic inward pacemaker currents with the removal of external Ca²⁺. In recording of intracellular Ca²⁺ concentrations using fluo 3-AM dye, carbachol increased intracellular Ca²⁺ concentrations with increasing of Ca²⁺ oscillations. These results suggest that carbachol modulates the pacemaker activity of ICC through the activation of non-selective cation channels via muscarinic M₃ receptors by a G-protein dependent intracellular Ca²⁺ release mechanism.     

Hesperidin depolarizes the pacemaker potentials through 5-HT4 receptor in murine small intestinal interstitial cells of Cajal

ABSTRACT

Hesperidin, a citrus flavonoid, can exert numerous beneficial effects on human health. Interstitial cells of Cajal (ICC) are pacemaker cells in the gastrointestinal (GI) tract. In the present study, we investigated potential effects of hesperidin on pacemaker potential of ICC in murine small intestine and GI motility. A whole-cell patch-clamp configuration was used to record pacemaker potential in ICC, and GI motility was investigated in vivo by recording gastric emptying (GE) and intestinal transit rate (ITR). Hesperidin depolarized pacemaker potentials of ICC in a dose-dependent manner. Pre-treatment with methoctramine or 4-DAMP did not inhibit hesperidin-induced pacemaker potential depolarization. Neither a 5-HT₃ receptor antagonist (Y25130) nor a 5-HT₇ receptor antagonist (SB269970) reduced the effect of hesperidin on ICC pacemaker potential, whereas the 5-HT₄ receptor antagonist RS39604 was found to inhibit this effect. In the presence of GDP–β–S, hesperidin-induced pacemaker potential depolarization was inhibited. Moreover, in the presence of U73122 and calphostin C, hesperidin did not depolarize pacemaker potentials. Furthermore, hesperidin accelerated GE and ITR in vivo. These results imply that hesperidin depolarized ICC pacemaker potential via 5-HT₄ receptors, G protein, and PLC/PKC dependent pathways and that it increased GI motility. Therefore, hesperidin may be a promising novel drug to regulate GI motility.