RESUMEN
Constipation is a disorder of the gastrointestinal (GI) and some of the main etiological mechanisms are directly related to changes in GI physiology. The capacity to carry out paired assessments and measure GI parameters under the influence of constipation is a relevant point in selecting a suitable methodology. We aimed to perform a non-invasive investigation of gastrointestinal motility in constipated rats using the alternating current biosusceptometry system (ACB). The animals were split into two groups: the pre-induction stage (CONTROL) and post-induction loperamide stage (LOP). We assessed GI motility parameters using the ACB system. Colon morphometric and immunohistochemical analyses were performed for biomarkers (C-kit) for interstitial cells of Cajal (ICC). Our results showed a significant increase in gastrointestinal transit in the LOP group in addition to a reduction in the dominant frequency of gastric contraction and an arrhythmic profile. A change in colonic contractility profiles was observed, indicating colonic dysmotility in the LOP group. We found a reduction in the number of biomarkers for intestinal cells of Cajal (ICC) in the LOP group. The ACB system can evaluate transit irregularities and their degrees of severity, while also supporting research into novel, safer, and more efficient treatments for constipation.
Asunto(s)
Animales , Masculino , Ratas , Tracto Gastrointestinal/anomalías , Motilidad Gastrointestinal , Loperamida/efectos adversos , Estreñimiento/inducido químicamente , Células Intersticiales de Cajal/clasificaciónRESUMEN
OBJECTIVE@#To explore the effect of Tangshen Formula (, TSF), a Chinese herbal medicine, on interstitial cells of Cajal (ICC) in the colon of diabetic rats.@*METHODS@#Fifty-four male Wistar rats were randomly divided into normal control (NC, n=14) and high-fat diet (HFD) groups (n=40). After 6 weeks, the rats in the HFD group were injected intraperitoneally streptozotocin once (30 mg/kg). Thirty rats with fasting blood glucose higher than 11.7 mmol/L were randomly divided into diabetes (DM) and TSF groups, 15 rats in each group. Rats in the NC and DM groups were intragastrically administered with saline, and those in the TSF group were given with TSF (2.4 g/kg) once daily for 20 weeks. Expression levels of Bax, Bcl-2, and caspase-3 in colonic smooth muscle layer were measured by Western blotting and immunohistochemical staining. The number of ICC was determined by immunohistochemical staining. Immunofluorescence was used for analyzing the ratio of classically activated macrophages (M1) and alternatively activated macrophages (M2) to total macrophages. Electron microscopy was used to observe the epithelial ultrastructure and junctions.@*RESULTS@#TSF appeared to partially prevented loss of ICC in DM rats (P<0.05). Compared with the NC group, expression levels of Bcl-2, Bax, caspase-3, and TNF-α as well as the ratio of M1 to total macrophages increased in DM rats (all P<0.05), and the ratio of M2 to total macrophages decreased (P<0.05 or P<0.01). Compared with the DM group, TSF decreased the expression levels of abovementioned proteins and restore M2 to total macrophages ratio (P<0.05 or P<0.01). TSF appeared to attenuate the ultrastructural changes of epithelia and improve the tight and desmosome junctions between epithelia reduced in the DM rats.@*CONCLUSION@#Reduced number of ICC in DM rats may be associated with damage of the intestinal barrier. The protective effects of TSF on ICC may be through repair of the epithelial junctions, which attenuates inflammation and inflammation-initiated apoptosis in colon of DM rats.
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Animales , Masculino , Ratas , Colon , Diabetes Mellitus Experimental/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Células Intersticiales de Cajal , Ratas WistarRESUMEN
Introducción: Los tumores del estroma gastrointestinal son neoplasias de comportamiento benigno o maligno. Se originan de las células intersticiales de Cajal del tubo digestivo. Objetivo: Describir dos formas distintas de presentación clínica de los tumores del estroma gastrointestinal. Casos clínicos: El caso 1, paciente femenina de 65 años de edad que acudió por síntomas compresivos del tubo digestivo superior a causa de un gastrointestinal gástrico. El caso 2, paciente masculino de 56 años de edad que acudió por sangrado de tubo digestivo medio ocasionado por un gastrointestinal intestinal. Conclusiones: Los tumores del estroma gastrointestinal tienen distinta presentación clínica. Su tratamiento es esencialmente quirúrgico y en algunos casos complementados con terapia molecular dirigida(AU)
Introduction: Gastrointestinal stromal tumors are neoplasms of benign or malignant behavior. They originate from the interstitial cells of Cajal in the digestive tract. Objective: The objective of this work is to describe two different forms of clinical presentation. Case report: case 1: 65-year-old female patient who presented for compression symptoms of the upper digestive tract due to gastric GIST; case 2: 56-year-old male who presented with bleeding from the middle digestive tract caused by intestinal GIST. Conclusions: GISTs have different clinical presentation. Its treatment is essentially surgical and in some cases supplemented with targeted molecular therapy(AU)
Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Tumores del Estroma Gastrointestinal/cirugía , Células Intersticiales de Cajal , Terapia Molecular Dirigida , Informe de Investigación , Neoplasias Gastrointestinales/epidemiologíaRESUMEN
Los tumores del estroma gastrointestinal (TEGI) son las neoplasias mesenquimales más frecuentes del tracto digestivo con una frecuencia de 0,1 a 3 % de todas las neoplasias gastrointestinales. Son derivadas de las células intersticiales de Cajal, localizadas a lo largo del plexo mioentérico de la pared intestinal. Comprenden leiomisarcomas, leiomioblastomas, leimiomas, schwannomas. Están formadas por células fusiformes, en la mayoría, epitelioides o ambas. Se localizan predominantemente en estómago e intestino delgado. Inmunohistoquimicamente se detecta expresión de receptores KIT (antígeno CD117) que puede ser focal, variable o difusa. Involucran tumores benignos pero con potencial malignidad hasta sarcomas metastizantes. Su pronóstico se basa el tamaño y porcentaje de mitosis. La sintomatología depende del lugar de origen, en este caso como masa palpable abdominal y obstrucción intestinal. El tratamiento es la resección completa con márgenes limpios. En caso de metástasis preoperatoria, esta no cambia la conducta quirúrgica, debido a la posibilidad de obstrucción y sangrado. El Imatinib a dosis de 400 mg controla el crecimiento eventual de enfermedad residual. Se presenta el caso clínico de paciente con masa abdominal y cuadro de obstrucción intestinal que evoluciona a la perforación de un TEGI localizado en yeyuno proximal con cuadro peritoneal y absceso subfrenico. Se procede a resección intestinal con yeyuno yeyuno anastomosis resección completa. La histopatología reporta Tumor estronal gastrointestinal y la inmunohistoquimica Neoplasia Fusocelular. CONCLUSION: Los TEGI son de origen mesenquimal, comprenden espectro grande de tumores desde benignos, hasta carcomas altamente malignos. Los factores pronósticos se asocian al tamaño e índice mitótico del tumor. La inmunohistoquimica reporta su expresión para CD117. La resección quirúrgica completa es el pilar de tratamiento y en casos de resección incompleta o irresecabilidad puede usarse imatinib.
Gastrointestinal stromal tumors (GIST) are the most frequent mesenchymal neoplasms of the digestive tract with a frequency of 0.1 to 3% of all gastrointestinal neoplasms. They are derived from the interstitial cells of Cajal, located along the myoenteric plexus of the intestinal wall. They include leiomysarcomas, leiomioblastomas, leimiomas, schwannomas. They are made up of spindle cells, in the majority, epithelioids or both. They are located predominantly in the stomach and small intestine. Immunohistochemically, KIT receptor expression (CD117 antigen) is detected, and they can be focal, variable or diffuse. They involve benign but potentially malignancy tumors up to metastatic sarcomas. Their prognosis is based on the size and percentage of mitosis. The symptoms depend on the place of its origin. Treatment is complete resection with clean margins. In the case of preoperative metastases, this does not change the surgical approach, due to the possibility of obstruction and bleeding. Imatinib at a dose of 400 mg controls the eventual growth of residual disease. We present the clinical case of a patient with an abdominal mass and a small bowel obstruction that progresses to perforation of a GIST located in the proximal jejunum with a peritonitis and subphrenic abscess. Intestinal resection is performed with jejunum jejunoanastomosis and complete resection. Histopathology reports gastrointestinal stromal tumor and immunohistochemistry, Fusocellular neoplasia. Conclusion: GIST are of mesenchymal origin, they include a wide spectrum of tumors from benign to highly malignant sarcomas. Prognostic factors are associated with tumor size and mitotic index. Immunohistochemistry reports its expression for CD117. Complete surgical resection is the mainstay of treatment and in cases of incomplete resection or unresectability imatinib can be used.
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Absceso Subfrénico , Células Intersticiales de Cajal , Metástasis de la Neoplasia , Neoplasias , Terapéutica , Proteínas Proto-Oncogénicas c-kit , Tumores del Estroma GastrointestinalRESUMEN
Under physiological conditions, the motility of smooth muscle in digestive tract is mainly regulated by enteric nervous system (ENS). However, how neural signal is transmitted to smooth muscle is not fully understood. Autonomic nerve endings in the smooth muscle layer form large number of varicosities which contain neurotransmitters. It was considered that nerve pulses arriving at the varicosities may cause the release of neurotransmitters, which may diffuse to the smooth muscle cells to induce contractile or relaxant responses. Over the past decade, a new understanding of the neurotransmission between ENS and smooth muscle has emerged, which emphasizes the role of a functional syncytium consisting of the interstitial cells of Cajal (ICC), the platelet-derived growth factor receptor α positive (PDGFRα) cells and the smooth muscle cells. Within the syncytium, purine neurotransmitters bind to P2Y1 receptors on PDGFRα cells, activating small-conductance calcium activated potassium channel (SK3) to hyperpolarize PDGFRα cells, and thus hyperpolarize smooth muscle cells through gap junction, resulting in relaxation of smooth muscle. In this paper, we review the research progress in the field of inhibitory purinergic neurotransmission in the gastrointestinal tract.
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Células Intersticiales de Cajal , Músculo Liso , Miocitos del Músculo Liso , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas , Transmisión SinápticaRESUMEN
ABSTRACT BACKGROUND: Serotonin (5-HT) is present in the epithelial enterochromaffin cells (EC), mast cells of the lamina propria and enteric neurons. The 5-HT is involved in regulating motility, secretion, gut sensation, immune system and inflammation. OBJECTIVE: Evaluate the effects of diabetes and quercetin supplementation on serotoninergic cells and its cell loss by apoptosis in jejunal mucosa of streptozotocin-induced diabetic rats (STZ-rats). METHODS: Twenty-four male Wistar rats were divided into four groups: normoglycemic (C), normoglycemic supplemented with 40 mg/day quercetin (Q), diabetic (D) and diabetic supplemented with 40 mg/day quercetin (DQ). After 120 days, the jejunum was collected and fixated in Zamboni's solution for 18 h. After obtaining cryosections, immunohistochemistry was performed to label 5-HT and caspase-3. Quantification of 5-HT and caspase-3 immunoreactive (IR) cells in the lamina propria, villi and crypts were performed. RESULTS: The diabetic condition displayed an increase of the number of 5-HT-IR cells in villi and crypts, while decreased number of these cells was observed in lamina propria in the jejunum of STZ-rats. In the diabetic animals, an increased density of apoptotic cells in epithelial villi and crypts of the jejunum was observed, whereas a decreased number of caspase-3-IR cells was observed in lamina propria. Possibly, quercetin supplementation slightly suppressed the apoptosis phenomena in the epithelial villi and crypts of the STZ-rats, however the opposite effect was observed on the 5-HT-IR cells of the lamina propria. Quercetin supplementation on healthy animals promoted few changes of serotoninergic function and apoptotic stimuli. CONCLUSION: These results suggest that quercetin supplementation mostly improved the serotonergic function affected by diabetes maybe due to antioxidant and anti-inflammatory properties of quercetin.
RESUMO CONTEXTO: A serotonina (5-HT) está presente nas células epiteliais enterocromafins (CE), nos mastócitos da lâmina própria e nos neurônios entéricos. A 5-HT está envolvida na regulação da motilidade, secreção, nocepção intestinal, sistema imunológico e inflamação. Objetivo: Avaliar os efeitos do diabetes e da suplementação de quercetina sobre a função serotoninérgica e a perda celular por apoptose na mucosa jejunal de ratos diabéticos induzidos por estreptozotocina (ratos STZ). MÉTODOS: Vinte e quatro ratos Wistar machos foram divididos em quatro grupos: normoglicêmico (C), normoglicêmico suplementado com quercetina 40 mg/dia (Q), diabético (D) e diabético suplementado com quercetina 40 mg/dia (DQ). Após 120 dias, o jejuno foi coletado e fixado na solução de Zamboni por 18 horas. Após a obtenção de cortes em criostato, a imuno-histoquímica foi realizada para marcar 5-HT e caspase-3. A quantificação de células imunorreativas (IR) à 5-HT e caspase-3 foram realizadas na lâmina própria, vilosidades e criptas. RESULTADOS: A condição diabética ocasionou um aumento do número de células 5-HT-IR nas vilosidades e criptas, enquanto que na lâmina própria houve uma redução dessas células, no jejuno de ratos STZ. Nos animais diabéticos, foi observada uma densidade aumentada de células apoptóticas no epitélio do jejuno, tanto nas vilosidades quanto nas criptas, por outro lado um número reduzido de células caspase-3-IR foi observado na lâmina própria. Possivelmente, a suplementação de quercetina suprimiu ligeiramente os fenômenos de apoptose no epitélio de vilosidades e criptas do jejuno de ratos STZ, no entanto, o efeito oposto foi observado nas células 5-HT-IR da lâmina própria. A suplementação com quercetina em animais saudáveis promoveu poucas alterações na função serotoninérgica e nos estímulos apoptóticos. CONCLUSÃO: Estes resultados sugerem que a suplementação de quercetina melhorou principalmente a função serotoninérgica afetada pelo diabetes, talvez devido às propriedades antioxidantes e anti-inflamatórias da quercetina.
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Animales , Masculino , Ratas , Quercetina/administración & dosificación , Serotonina/metabolismo , Apoptosis/efectos de los fármacos , Suplementos Dietéticos , Diabetes Mellitus Experimental/tratamiento farmacológico , Caspasa 3/metabolismo , Yeyuno/patología , Antioxidantes/administración & dosificación , Inmunohistoquímica , Ratas Wistar , Diabetes Mellitus Experimental/patología , Células Intersticiales de Cajal/efectos de los fármacos , Células Intersticiales de Cajal/patología , Mucosa Intestinal/efectos de los fármacos , Yeyuno/efectos de los fármacosRESUMEN
To determine the effect of a recombinant lentivirus containing human stem cell leukemia (SCL) gene on the expression of c-kit protein in damaged interstitial cells of Cajal (ICC) under high glucose condition. Methods: After isolation of ICC, the cells were cultured for 24 hours until the cells were adherent. After identification by inverted microscope and immunofluorescence, ICC cells were divided into two groups: A control group and a high glucose group. The control group was added with a medium containing 5 mmol/L of glucose. The high glucose group was added with a medium containing 20 mmol/L of glucose. After 48 h of continuous cultivation, the high glucose group was divided into 3 subgroups: A blank group, an empty lentivirus group, and an experimental group. The blank group, the empty lentivirus group, and the experimental group were added a medium containing PBS solution, empty lentivirus, and a recombinant lentivirus containing the SCL gene with a glucose concentration of 5 mmol/L, respectively. The cultures were incubated for 24 and 48 h. The expression of c-kit protein in ICC in each group was detected by Western blot. Results: After 24 or 48 h, the expression of c-kit protein in ICC was significantly lower in the blank group and the lentivirus group than that in the control group, and the expression of c-kit protein in ICC was significantly higher in the experimental group than that in the blank group and the empty lentivirus group, but it was still lower than that in the control group (all P<0.05). Conclusion: The recombinant lentivirus of SCL gene can up-regulate the expression of c-kit protein in functionally impaired ICC under high glucose condition.
Asunto(s)
Humanos , Glucosa , Células Intersticiales de Cajal , Lentivirus , Leucemia Mieloide Aguda , Proteínas Proto-Oncogénicas c-kitRESUMEN
BACKGROUND/AIMS: Interstitial cells of Cajal (ICC) and their special calcium-activated chloride channel, anoctamin-1 (ANO1) play pivotal roles in regulating colonic transit. This study is designed to investigate the role of ICC and the ANO1 channel in colonic transit disorder in dextran sodium sulfate (DSS)-treated colitis mice. METHODS: Colonic transit experiment, colonic migrating motor complexes (CMMCs), smooth muscle spontaneous contractile experiments, intracellular electrical recordings, western blotting analysis, and quantitative polymerase chain reaction were applied in this study. RESULTS: The mRNA and protein expressions of c-KIT and ANO1 channels were significantly decreased in the colons of DSS-colitis mice. The colonic artificial fecal-pellet transit experiment in vitro was significantly delayed in DSS-colitis mice. The CMMCs and smooth muscle spontaneous contractions were significantly decreased by 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB), an ANO1 channel blocker, and NG-Nitro-L-arginine methyl ester hydrochloride (L-NAME), an inhibitor of nitric oxide synthase activity, in DSS-colitis mice compared with that of control mice. Intracellular electrical recordings showed that the amplitude of NPPB-induced hyperpolarization was more positive in DSS-colitis mice. The electric field stimulation-elicited nitric-dependent slow inhibitory junctional potentials were also more positive in DSS-colitis mice than those of control mice. CONCLUSION: The results suggest that colonic transit disorder is mediated via downregulation of the nitric oxide/ICC/ANO1 signalling pathway in DSS-colitis mice.
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Animales , Ratones , Western Blotting , Canales de Cloruro , Colitis , Colon , Dextranos , Regulación hacia Abajo , Técnicas In Vitro , Células Intersticiales de Cajal , Músculo Liso , Complejo Mioeléctrico Migratorio , NG-Nitroarginina Metil Éster , Óxido Nítrico Sintasa , Reacción en Cadena de la Polimerasa , ARN Mensajero , SodioRESUMEN
BACKGROUND/AIMS: It is now recognised that gastric dysrhythmias are best characterised by their spatial propagation pattern. Hyperglycemia is an important cause of gastric slow wave dysrhythmia, however, the spatiotemporal patterns of dysrhythmias in this context have not been investigated. This study aims to investigate the relationship between hyperglycemia and the patterns of dysrhythmias by employing high-resolution (multi-electrode) mapping simultaneously at the anterior and posterior gastric serosa. METHODS: High-resolution mapping (8 × 16 electrodes per serosal) was performed in 4 anesthetized hounds. Baseline recordings (21 ± 8 minutes) were followed by intravenous injection of glucagon (0.5 mg per dose) and further recordings (59 ± 15 minutes). Blood glucose levels were monitored manually using a glucose sensing kit at regular 5-minute intervals. Slow wave activation maps, amplitudes, velocity, anisotropic ratio, and frequency were calculated. Differences were compared between baseline and post glucagon injection. RESULTS: Baseline slow waves propagated symmetrically and antegrade. The blood glucose levels were increased by an average of 112% compared to the baseline by the end of the recordings. All subjects demonstrated elevated incidence of slow wave dysrhythmias following injection compared to the baseline (48 ± 23% vs 6 ± 4%, P < 0.05). Dysrhythmias arose simultaneously or independently on anterior and posterior serosa. Spatial dysrhythmias occurred before and persisted after the onset and disappearance of temporal dysrhythmias. CONCLUSIONS: Infusion of glucagon induced gastric slow wave dysrhythmias, which occurred across a heterogeneous range of patterns and frequencies. The spatial dysrhythmias of gastric slow waves were shown to be more prevalent and persisted over a longer period of time compared to the temporal dysrhythmias.
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Glucemia , Electrodos , Electrofisiología , Tracto Gastrointestinal , Glucagón , Glucosa , Hiperglucemia , Incidencia , Inyecciones Intravenosas , Células Intersticiales de Cajal , Complejo Mioeléctrico Migratorio , Membrana SerosaRESUMEN
The internal anal sphincter (IAS) plays an important role in the maintenance of fecal continence since it generates tone and is responsible for > 70% of resting anal pressure. During normal defecation the IAS relaxes. Historically, tone generation in gastrointestinal muscles was attributed to mechanisms arising directly from smooth muscle cells, ie, myogenic activity. However, slow waves are now known to play a fundamental role in regulating gastrointestinal motility and these electrical events are generated by the interstitial cells of Cajal. Recently, interstitial cells of Cajal, as well as slow waves, have also been identified in the IAS making them viable candidates for tone generation. In this review we discuss four different mechanisms that likely contribute to tone generation in the IAS. Three of these involve membrane potential, L-type Ca²⁺ channels and electromechanical coupling (ie, summation of asynchronous phasic activity, partial tetanus, and window current), whereas the fourth involves the regulation of myofilament Ca²⁺ sensitivity. Contractile activity in the IAS is also modulated by sympathetic motor neurons that significantly increase tone and anal pressure, as well as inhibitory motor neurons (particularly nitrergic and vasoactive intestinal peptidergic) that abolish contraction and assist with normal defecation. Alterations in IAS motility are associated with disorders such as fecal incontinence and anal fissures that significantly decrease the quality of life. Understanding in greater detail how tone is regulated in the IAS is important for developing more effective treatment strategies for these debilitating defecation disorders.
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Canal Anal , Defecación , Incontinencia Fecal , Motilidad Gastrointestinal , Células Intersticiales de Cajal , Potenciales de la Membrana , Neuronas Motoras , Músculo Liso , Músculos , Miocitos del Músculo Liso , Miofibrillas , Calidad de Vida , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas , TétanosRESUMEN
BACKGROUND/AIMS: Interstitial cells play important roles in gastrointestinal (GI) neuro-smooth muscle transmission. The underlying mechanisms of colonic dysmotility have not been well illustrated. We established a partial colon obstruction (PCO) mouse model to investigate the changes of interstitial cells and the correlation with colonic motility. METHODS: Western blot technique was employed to observe the protein expressions of Kit, platelet-derived growth factor receptor-α (Pdgfra), Ca²⁺-activated Cl⁻ (Ano1) channels, and small conductance Ca²⁺- activated K⁺ (SK) channels. Colonic migrating motor complexes (CMMCs) and isometric force measurements were employed in control mice and PCO mice. RESULTS: PCO mice showed distended abdomen and feces excretion was significantly reduced. Anatomically, the colon above the obstructive silicone ring was obviously dilated. Kit and Ano1 proteins in the colonic smooth muscle layer of the PCO colons were significantly decreased, while the expression of Pdgfra and SK3 proteins were significantly increased. The effects of a nitric oxide synthase inhibitor (L-NAME) and an Ano1 channel inhibitor (NPPB) on CMMC and colonic spontaneous contractions were decreased in the proximal and distal colons of PCO mice. The SK agonist, CyPPA and antagonist, apamin in PCO mice showed more effect to the CMMCs and colonic smooth muscle contractions. CONCLUSIONS: Colonic transit disorder may be due to the downregulation of the Kit and Ano1 channels and the upregulation of SK3 channels in platelet-derived growth factor receptor-α positive (PDGFRα⁺) cells. The imbalance between interstitial cells of Cajal-Ano1 and PDGFRα-SK3 distribution might be a potential reason for the colonic dysmotility.
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Animales , Ratones , Abdomen , Apamina , Western Blotting , Canales de Cloruro , Colon , Regulación hacia Abajo , Heces , Células Intersticiales de Cajal , Músculo Liso , Complejo Mioeléctrico Migratorio , Óxido Nítrico Sintasa , Factor de Crecimiento Derivado de Plaquetas , Silicio , Siliconas , Canales de Potasio de Pequeña Conductancia Activados por el Calcio , Regulación hacia ArribaRESUMEN
The objective was to study the effect of mechanical intestinal obstruction in rats on the phenotype of interstitial cells of Cajal (ICC). Healthy Wistar rats were randomly divided into sham-operation group (C), one day obstruction group (M1), two days obstruction group (M2), and three days obstruction group (M3), with 10 rats in each group. The expression of SCF mRNA and c-Kit protein in intestinal tissue was investigated by RT-PCR and immunohistochemistry. Compared with the sham-operation group, the relative expression of SCF mRNA and the expression of c-Kit protein in intestinal tissue were significantly decreased in both obstruction groups. Levels decreased gradually with the prolongation of obstruction time, and significantly decreased on the 3rd day after obstruction (P<0.05). Immunohistochemical staining of the small intestine showed that the number of ICC in the sham-operation group was the highest, and they were gradually decreased with the extension of obstruction time in the M1 to M3 groups. There was a significant difference between groups (P<0.05). Intestinal obstruction caused a decrease in the concentrations of SCF mRNA and c-Kit protein in ICC. With the prolongation of intestinal obstruction, the number of ICCs gradually decreased.
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Animales , Masculino , Ratas , ARN Mensajero/metabolismo , Factor de Células Madre/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células Intersticiales de Cajal/metabolismo , Obstrucción Intestinal/metabolismo , Fenotipo , Inmunohistoquímica , Ratas Wistar , Modelos Animales de Enfermedad , Células Intersticiales de Cajal/patología , Obstrucción Intestinal/patologíaRESUMEN
BACKGROUND/AIMS: We investigated the role of representative endoplasmic reticulum proteins, stromal interaction molecule 1 (STIM1), and store-operated calcium entry-associated regulatory factor (SARAF) in pacemaker activity in cultured interstitial cells of Cajal (ICCs) isolated from mouse small intestine. METHODS: The whole-cell patch clamp technique applied for intracellular calcium ions ([Ca²+]i) analysis with STIM1 or SARAF overexpressed cultured ICCs from mouse small intestine. RESULTS: In the current-clamping mode, cultured ICCs displayed spontaneous pacemaker potentials. External carbachol exposure produced tonic membrane depolarization in the current-clamp mode, which recovered within a few seconds into normal pacemaker potentials. In STIM1-overexpressing cultured ICCs pacemaker potential frequency was increased, and in SARAF-overexpressing ICCs pacemaker potential frequency was strongly inhibited. The application of gadolinium (a non-selective cation channel inhibitor) or a Ca2+-free solution to understand Orai channel involvement abolished the generation of pacemaker potentials. When recording intracellular Ca²+ concentration with Fluo 3-AM, STIM1-overexpressing ICCs showed an increased number of spontaneous intracellular Ca²+ oscillations. However, SARAF-overexpressing ICCs showed fewer spontaneous intracellular Ca2+ oscillations. CONCLUSION: Endoplasmic reticulum proteins modulated the frequency of pacemaker activity in ICCs, and levels of STIM1 and SARAF may determine slow wave patterns in the gastrointestinal tract.
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Animales , Ratones , Calcio , Carbacol , Retículo Endoplásmico , Gadolinio , Motilidad Gastrointestinal , Tracto Gastrointestinal , Células Intersticiales de Cajal , Intestino Delgado , Iones , MembranasRESUMEN
No abstract available.
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Animales , Ratas , Envejecimiento , Colon , Estreñimiento , Células Intersticiales de CajalRESUMEN
No abstract available.
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Animales , Ratones , Calcio , Células Intersticiales de Cajal , YeyunoRESUMEN
BACKGROUND/AIMS: Irritable bowel syndrome (IBS) is a common disease characterized by intestinal dysmotility, the mechanism of which remains elusive. We aim to determine whether the high-affinity choline transporter 1 (CHT1), a determinant of cholinergic signaling capacity, modulates intestinal motility associated with stress-induced IBS. METHODS: A rat IBS model was established using chronic water avoidance stress (WAS). Colonic pathological alterations were evaluated histologically and intestinal motility was assessed by intestinal transit time and fecal water content (FWC). Visceral sensitivity was determined by visceromotor response to colorectal distension. RT-PCR, western blotting, and immunostaining were performed to identify colonic CHT1 expression. Contractility of colonic muscle strips was measured using isometric transducers. enzyme-linked immunosorbent assay was used to measure acetylcholine (ACh). We examined the effects of MKC-231, a choline uptake enhancer, on colonic motility. RESULTS: After 10 days of WAS, intestinal transit time was decreased and fecal water content increased. Visceromotor response magnitude in WAS rats in response to colorectal distension was significantly enhanced. Protein and mRNA CHT1 levels in the colon were markedly elevated after WAS. The density of CHT1-positive intramuscular interstitial cells of Cajal and myenteric plexus neurons in WAS rats was higher than in controls. Ammonium pyrrolidine dithiocarbamate partly reversed CHT1 upregulation and alleviated colonic hypermotility in WAS rats. Pharmacological enhancement of CHT1 activity by MKC-231 enhanced colonic motility in control rats via upregulation of CHT1 and elevation of ACh production. CONCLUSION: Upregulation of CHT1 in intramuscular interstitial cells of Cajal and myenteric plexus neurons is implicated in chronic stress-induced colonic hypermotility by modulation of ACh synthesis via nuclear factor-kappa B signaling.
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Animales , Ratas , Acetilcolina , Compuestos de Amonio , Western Blotting , Colina , Colon , Ensayo de Inmunoadsorción Enzimática , Motilidad Gastrointestinal , Células Intersticiales de Cajal , Síndrome del Colon Irritable , Modelos Animales , Plexo Mientérico , Neuronas , ARN Mensajero , Transductores , Regulación hacia Arriba , AguaRESUMEN
Purinergic receptors play an important role in regulating gastrointestinal (GI) motility. Interstitial cells of Cajal (ICCs) are pacemaker cells that regulate GI smooth muscle activity. We studied the functional roles of external adenosine 5′-triphosphate (ATP) on pacemaker activity in cultured ICCs from mouse small intestines by using the whole-cell patch clamp technique and intracellular Ca²⁺ ([Ca²⁺]ᵢ) imaging. External ATP dose-dependently depolarized the resting membrane and produced tonic inward pacemaker currents, and these effects were antagonized by suramin, a purinergic P2 receptor antagonist. ATP-induced effects on pacemaker currents were suppressed by an external Na⁺-free solution and inhibited by the nonselective cation channel blockers, flufenamic acid and niflumic acid. The removal of external Ca²⁺ or treatment with thapsigargin (inhibitor of Ca²⁺ uptake into endoplasmic reticulum) inhibited the ATP-induced effects on pacemaker currents. Spontaneous [Ca²⁺]ᵢ oscillations were enhanced by external ATP. These results suggest that external ATP modulates pacemaker activity by activating nonselective cation channels via external Ca²⁺ influx and [Ca²⁺]ᵢ release from the endoplasmic reticulum. Thus, it seems that activating the purinergic P2 receptor may modulate GI motility by acting on ICCs in the small intestine.
Asunto(s)
Animales , Ratones , Adenosina , Adenosina Trifosfato , Retículo Endoplásmico , Ácido Flufenámico , Células Intersticiales de Cajal , Intestino Delgado , Membranas , Músculo Liso , Ácido Niflúmico , Marcapaso Artificial , Receptores Purinérgicos , Receptores Purinérgicos P2 , Suramina , TapsigarginaRESUMEN
Ulcerative colitis is a chronic inflammatory disease of the colon where intestinal motility is disturbed. Interstitial cells of Cajal (ICC) are required to maintain normal intestinal motility. In the present study, we assessed the effect of tumor necrosis factor-alpha (TNF-α) on viability and apoptosis of ICC, as well as on the expression of stem cell factor (SCF), ghrelin, and substance P. ICC were derived from the small intestines of Swiss albino mice. Cell viability and apoptosis were measured using CCK-8 assay and flow cytometry, respectively. ELISA was used to measure the concentrations of IL-1β, IL-6, ghrelin, substance P, and endothelin-1. Quantitative RT-PCR was used to measure the expression of SCF. Western blotting was used to measure the expression of apoptosis-related proteins, interleukins, SCF, and NF-κB signaling pathway proteins. TNF-α induced inflammatory injury in ICC by decreasing cell viability and increasing apoptosis and levels of IL-1β and IL-6. TNF-α decreased the levels of SCF, ghrelin, and substance P, but had no effect on endothelin-1. TNF-α down-regulated expressions of SCF, ghrelin, and substance P by activating the NF-κB pathway in ICC. In conclusion, TNF-α down-regulated the expressions of SCF, ghrelin, and substance P via the activation of the NF-κB pathway in ICC.
Asunto(s)
Animales , Masculino , Ratones , Ghrelina/metabolismo , Células Intersticiales de Cajal/efectos de los fármacos , FN-kappa B/metabolismo , Factor de Células Madre/metabolismo , Sustancia P/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Apoptosis/efectos de los fármacos , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Motilidad Gastrointestinal/efectos de los fármacos , Ghrelina/antagonistas & inhibidores , Células Intersticiales de Cajal/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal/efectos de los fármacosRESUMEN
The effect of bisacodyl on the treatment of rats with slow transit constipation (STC) was studied. Forty-five female Wister rats were divided into control group, STC group, and STC bisacodyl group. The immunohistochemical method was used to determine interstitial cells of Cajal (ICC) and the expression of c-Kit protein. Body mass and the number of defecations were significantly decreased in the STC group compared with the control group on the 100th day after diphenoxylate administration, while dry weight of feces was significantly increased and the intestinal transit time was prolonged. There were significant differences in the number of defecations, dry weight of feces, and intestinal transit time among the three groups. The number of defecations was higher, dry weight of feces was lower, and intestinal transit time was shorter in the STC bisacodyl group compared to the STC group. In addition, ICC basement membrane dissolution occurred in the colon wall of the STC group. The connection between ICC and surrounding cells was destroyed, and the nucleus shrunken to different degrees. Moreover, c-Kit expression in the STC group was significantly lower than the control group. The connection between ICC and surrounding cells in the STC bisacodyl group was significantly stronger than the STC group, and the number of ICC and the expression of c-Kit were increased. Bisacodyl could reduce the severity of STC in rats by increasing the number of ICC and the expression of c-Kit.