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1.
Gynecol Oncol ; 152(2): 235-242, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30466805

RESUMEN

OBJECTIVE: Surgical assessment of residual tumor provides the strongest prognostic information in advanced ovarian cancer (AOC), with the best outcome observed after complete resection. Postoperative radiological assessment before initiation of chemotherapy can supplement the information obtained by surgical assessment; however, it may also reveal conflicting findings. METHODS: Patients with AOC enrolled in the AGO-OVAR 12 trial underwent baseline imaging before the first chemotherapy cycle. The findings from surgical and radiologic assessment for disease extend were compared. Additionally, an integrated approach was assessed. RESULTS: Complete data from all 3 assessment methods were available for 1345 patients. Of 689 patients with complete resection, tumor was observed in 28% and 22% of patients undergoing radiologic and integrated assessment, respectively. Patients with surgical- radiological and surgical-integrated concordant findings showed a 5-year overall survival (5Y-OS) of 72% and 71%, whereas patients with surgical-radiological and surgical-integrated discordant results showed inferior 5Y-OS of 47% and 49%, respectively. Patients with surgically assessed residual disease had a 5-YOS of 37%. The interval between surgery and baseline assessment was independently associated with discordance between assessment methods, which might reflect early tumor regrowth. CONCLUSIONS: Baseline tumor assessment before chemotherapy provides information that stratifies patients with complete resection into different prognostic groups. Integrating the data from different assessment methods might lead to improved definitions of prognostic groups. Further investigation to determine if earlier initiation of chemotherapy after debulking surgery could increase survival of patients with early tumor regrowth is warranted.


Asunto(s)
Carcinoma Epitelial de Ovario/patología , Carcinoma Epitelial de Ovario/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/administración & dosificación , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Carcinoma Epitelial de Ovario/mortalidad , Método Doble Ciego , Femenino , Humanos , Indoles/administración & dosificación , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasia Residual/patología , Paclitaxel/administración & dosificación , Pronóstico , Adulto Joven
2.
Br J Cancer ; 107(2): 280-6, 2012 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-22699824

RESUMEN

BACKGROUND: BI 2536, a novel Polo-like kinase 1 inhibitor, was assessed in patients with unresectable advanced exocrine adenocarcinoma of the pancreas. METHODS: The study employed a two-stage design. Randomised first-line patients received BI 2536 200 mg on day 1 (n=43) or 60 mg on days 1-3 (n=43) every 21 days. Recruitment of second-line patients was planned for a second stage dependent on an interim analysis demonstrating ≥ 2 responses in the first 18 evaluable patients following 12 weeks of treatment and/or tumour control ≥ 12 weeks in 5 patients per schedule. Primary end point was objective response rate (ORR). RESULTS: By independent review, ORR was 2.3% (all partial) and 24.4% had stable disease as confirmed best response. The second stage was not initiated. Median overall and progression-free survivals were 149 (95% confidence interval (CI), 91-307) and 46 days (95% CI, 44-56). Most common drug-related adverse events were neutropenia (37.2%), leukopenia (29.1%), fatigue (29.1%) and nausea (22.1%); most common grade 3/4-related events were neutropenia (36.0%), leukopenia (27.9%) and thrombocytopenia (8.1%). CONCLUSION: Given the low ORR and poor survival, further development of BI 2536 monotherapy is not warranted in this population.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Proteínas de Ciclo Celular/antagonistas & inhibidores , Neoplasias Pancreáticas/tratamiento farmacológico , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Pteridinas/uso terapéutico , Adenocarcinoma/enzimología , Adenocarcinoma/metabolismo , Anciano , Proteínas de Ciclo Celular/metabolismo , Estudios de Cohortes , Intervalos de Confianza , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/enzimología , Neoplasias Pancreáticas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Pteridinas/efectos adversos , Pteridinas/farmacocinética , Quinasa Tipo Polo 1
3.
Langenbecks Arch Surg ; 391(2): 157-60, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16465554

RESUMEN

BACKGROUND: Abdominal gas gangrene caused by clostridia species is rare and usually associated with organ perforation, immune suppression, or advanced malignoma. CASE REPORT: A 61-year-old man was admitted with severe back pain 1 day after uncomplicated colonoscopic polypectomy. With the exception of preexisting minor depression, the patient had been previously in excellent health. The computed tomography scan showed retroperitoneal emphysema in the left psoas muscle. During exploratory laparotomy, a spreading retroperitoneal phlegmon with pneumoretroperitoneum and a secondary peritonitis were found. A macroscopic perforation of the gut, particularly at the polypectomy sites was excluded. After the operation, the patient evolved in a septic shock condition and had pulmonary failure. Before hyperbaric oxygen therapy could be employed, the patient died. The autopsy showed a massive gas gangrene of the retroperitoneum caused by Clostridium perfringens, but no macroscopic bowel perforation was detected. RESULTS: This is the first report of a case of gas gangrene after uncomplicated polypectomy without macroscopic perforation in an otherwise healthy individual. A microperforation due to mucosal defect after polypectomy was most likely the entry point for the bacteria. CONCLUSION: We conclude that clostridial myonecrosis should be considered in unclear abdominal infections, even if the patient's history is not typical as in the present case.


Asunto(s)
Clostridium perfringens , Enfermedades del Colon/etiología , Pólipos del Colon/cirugía , Colonoscopía/efectos adversos , Gangrena Gaseosa/diagnóstico , Perforación Intestinal/etiología , Enfermedades del Colon/cirugía , Resultado Fatal , Gangrena Gaseosa/microbiología , Gangrena Gaseosa/terapia , Humanos , Perforación Intestinal/cirugía , Masculino , Persona de Mediana Edad , Espacio Retroperitoneal , Choque Séptico/etiología , Choque Séptico/terapia , Tomografía Computarizada por Rayos X
6.
Gut ; 51(2): 155-63, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12117872

RESUMEN

BACKGROUND AND AIMS: Mucosal flattening and epithelial cell apoptosis are typical features of T cell induced inflammatory diseases of the bowel, such as coeliac disease and graft versus host disease. Mice injected with a T cell activating anti-CD3 antibody develop a severe diarrhoeal illness. We describe the histological features of this enteropathy and define the effector mechanisms involved in T cell induced mucosal injury in this in vivo model. METHODS: Wild-type and genetically modified mice were injected with the anti-CD3 antibody 3C11 (50 microg). Changes in the murine intestine were characterised by light microscopy analysis and terminal uridine nick-end labelling (TUNEL) assay. The role of perforin, Fas/Fas ligand (FasL), tumour necrosis factor alpha (TNF-alpha), and interferon gamma (IFN-gamma) in T cell induced mucosal damage was assessed using selected immunodeficient mouse strains. RESULTS: T cell activation caused severe damage, including small intestinal mucosal flattening and apoptosis of crypt epithelial cells. Mucosal damage was unaltered in anti-CD3 treated mice lacking IFN-gamma, Fas, or TNF-alpha receptors. In mice lacking TNF-alpha receptors and Fas (TNF-R1xR2 lpr/lpr strain), enterocyte apoptosis was diminished but there was no significant reduction in tissue damage. Apoptosis and mucosal injury were significantly reduced in perforin knockout mice. Abrogation of both FasL and perforin (perforin KOxgld mice) further significantly reduced tissue damage and apoptotic bodies. CONCLUSIONS: T cell induced mucosal injury is mediated by the combined effect of multiple pathways but predominantly by perforin. The redundancy of the mechanisms of tissue damage will have significant impact on therapeutic strategies aimed at specific and targeted inhibition of inflammatory processes.


Asunto(s)
Mucosa Intestinal/inmunología , Glicoproteínas de Membrana/fisiología , Linfocitos T/inmunología , Factor de Necrosis Tumoral alfa/fisiología , Animales , Anticuerpos Monoclonales/farmacología , Antígenos CD/genética , Apoptosis , Complejo CD3/inmunología , Epitelio/patología , Proteína Ligando Fas , Etiquetado Corte-Fin in Situ , Interferón gamma/genética , Mucosa Intestinal/patología , Intestino Delgado/inmunología , Activación de Linfocitos , Glicoproteínas de Membrana/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones SCID , Modelos Animales , Perforina , Proteínas Citotóxicas Formadoras de Poros , Receptores del Factor de Necrosis Tumoral/genética , Receptores Tipo I de Factores de Necrosis Tumoral , Receptores Tipo II del Factor de Necrosis Tumoral , Factor de Necrosis Tumoral alfa/genética
7.
J Mol Endocrinol ; 28(2): 99-110, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11932207

RESUMEN

We investigated the role of hepatocyte growth factor (HGF) in beta-cell growth and its complex intracellular signal transduction pathways. Cell proliferation was measured in the beta-cell line INS-1 using [3H]thymidine incorporation. Activation of mitogenic signaling proteins was assessed using co-immunoprecipitation, immunoblot analysis and specific protein activity inhibitors in proliferation assays. HGF (1 x 375 nM) increased INS-1 cell proliferation in the presence of 3-24 mM glucose up to 45-fold vs unstimulated controls. HGF exceeded the effect of glucose alone (2 x 2-fold at 3 mM glucose and 1 x 7-fold in the presence of 15 mM glucose). The HGF-induced INS-1 cell proliferation was further increased by addition of IGF-I or GH. Stimulation with HGF activated the JAK-2/STAT-5 pathway with a subsequent activation of phosphatidylinositol-3'-kinase (PI3'K). PI3'K activation was necessary for HGF- and glucose-stimulated INS-1 cell proliferation. The effect of PI3'K was mediated via 70 kDa S6 kinase and protein kinase B, which showed maximum activation in the presence of 3-6 mM glucose. Protein kinase C was essential for HGF-induced INS-1 cell proliferation. The HGF effect was also mediated at low glucose concentrations via insulin receptor substrate 4 (IRS-4) whereas other IRS proteins did not show any activation. High glucose concentrations also showed an increased IRS-4/PI3'K binding and therefore activation. In conclusion, beta-cell proliferation is mediated via complex interacting signal transduction pathways. HGF, in contrast to other growth factors, seems to be of importance particularly in the presence of low glucose concentrations and therefore takes a special role in this complex concert.


Asunto(s)
Glucosa/deficiencia , Factor de Crecimiento de Hepatocito/farmacología , Islotes Pancreáticos/citología , Islotes Pancreáticos/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , Inhibidores Enzimáticos/farmacología , Glucosa/metabolismo , Glucosa/farmacología , Hormona del Crecimiento/metabolismo , Hormona del Crecimiento/farmacología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Fosforilación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Timidina/metabolismo
8.
J Immunol ; 167(5): 2651-6, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11509607

RESUMEN

The intestinal mucosa normally displays minimal inflammation despite the close proximity between mucosal macrophages and lumenal bacteria. Macrophages interact with bacteria and their products through CD14, a surface receptor involved in the response to LPS, and CD89, the receptor for IgA (FcalphaR). Here we show that resident macrophages isolated from normal human intestine lack CD14 and CD89. The absence of CD14 and CD89 was not due to the isolation procedure or mucosal cell products, but was evident at the transcriptional level, as the macrophages expressed neither CD14- nor CD89-specific mRNAs, but did express Toll-like receptor 2 and 4 transcripts. Consistent with their CD14(-) phenotype, lamina propria macrophages displayed markedly reduced LPS-induced cytokine production and LPS-enhanced phagocytosis. In addition, IgA-enhanced phagocytosis was sharply reduced in lamina propria macrophages. Thus, the absence of CD14 and CD89 on resident intestinal macrophages, due to down-regulated gene transcription, causes down-modulated LPS- and IgA-mediated functions and probably contributes to the low level of inflammation in normal human intestinal mucosa.


Asunto(s)
Antígenos CD/metabolismo , Proteínas de Drosophila , Mucosa Intestinal/citología , Mucosa Intestinal/inmunología , Receptores de Lipopolisacáridos/metabolismo , Macrófagos/inmunología , Receptores Fc/metabolismo , Antígenos CD/genética , Secuencia de Bases , Citocinas/biosíntesis , Cartilla de ADN/genética , Regulación hacia Abajo , Humanos , Inmunoglobulina A/metabolismo , Técnicas In Vitro , Yeyuno/citología , Yeyuno/inmunología , Receptores de Lipopolisacáridos/genética , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Fagocitosis/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Receptores Fc/genética , Transducción de Señal , Receptor Toll-Like 2 , Receptores Toll-Like
9.
Ther Umsch ; 56(10): 597-601, 1999 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-10549232

RESUMEN

Abdominal complaints during pregnancy are frequent. In most instances, nausea and vomiting are a consequence of pregnancy and are considered indicators of a well-developing pregnancy. The growing uterus and hormonal changes during pregnancy often lead to gastroesophageal reflux and constipation. Serious gastrointestinal diseases such as intestinal obstruction or the exacerbation of a chronic inflammatory bowel disease during pregnancy are rare, but if suspected, often warrant immediate confirmation and aggressive therapy. Unnecessary delays are associated with an increasing mortality and morbidity.


Asunto(s)
Enfermedades Gastrointestinales/diagnóstico , Enfermedades Gastrointestinales/terapia , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/terapia , Adulto , Femenino , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/terapia , Fármacos Gastrointestinales/uso terapéutico , Humanos , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/terapia , Úlcera Péptica/diagnóstico , Úlcera Péptica/terapia , Embarazo
10.
Dtsch Med Wochenschr ; 124(42): 1235-8, 1999 Oct 22.
Artículo en Alemán | MEDLINE | ID: mdl-10572532

RESUMEN

HISTORY AND FINDINGS: A 17-year old adolescent with chronic constipation developed fecal incontinence with liquid, fetid stool. He had had variable bowel symptoms since early childhood, but not in his infancy. Since several years he had undergone psychotherapeutic treatment for depression due to a familial conflict situation. Abdominal palpation revealed the presence of a large, hard mass in the lower abdomen, measuring about 20 cm in diameter. INVESTIGATIONS: A defecography verified the presence of a huge obstructing fecalith in the rectum, with massive dilation and elongation of the antecedent rectum and colon (megarectum and megacolon). Neither endoscopy nor radiological imaging revealed a narrow bowel segment. In sequential biopsies, no indication of aberrant innervation was found. The recto-anal inhibitory reflex could be elicited. TREATMENT AND COURSE: Restoration of the rectal passage was achieved by manual disimpaction in numerous sessions, supported by repeated rectal enemas. Subsequently, the patient had normal daily bowel movements for a few days. However, he had to be readmitted three weeks later because again a fecalith had formed, measuring 15 cm in diameter. A few days after discharge the patient hat not followed the exhortation to void ad least once per day. After renewed disimpaction he was referred to a psychosomatic clinic. CONCLUSION: Voluntary withholding of defecation can eventuate massive coprostasis and the development of megacolon and megarectum. In theses instances the major complaint may not be constipation but paradoxical diarrhea. A number of conditions have to be excluded before the diagnosis idiopathic megacolon can be confirmed. Treatment ist difficult and often necessitates prolonged and repetitious interventions.


Asunto(s)
Estreñimiento/complicaciones , Impactación Fecal/diagnóstico , Adolescente , Enfermedad Crónica , Diagnóstico Diferencial , Diarrea/etiología , Endoscopía , Enema , Impactación Fecal/complicaciones , Impactación Fecal/terapia , Incontinencia Fecal/etiología , Humanos , Masculino , Megacolon/diagnóstico , Recurrencia , Tomografía Computarizada por Rayos X
11.
Am J Physiol ; 276(3): R715-23, 1999 03.
Artículo en Inglés | MEDLINE | ID: mdl-10070131

RESUMEN

Specific in vivo T cell activation initiated by treatment with anti-CD3 antibodies leads to diarrhea and structural damage of the intestinal mucosa. In this study, the effect of T cell-induced mucosal damage on jejunal epithelial ion transport, muscle contractility, and neuronal ACh release was assessed in Ussing chambers, organ baths, and a specialized perfusion apparatus, respectively. Time-matched control mice received hamster serum containing irrelevant antibodies. Jejunal segments from anti-CD3-treated mice displayed a significantly elevated epithelial baseline short-circuit current (which indicates increased ion transport) and a concomitant reduction in responsiveness to prosecretory stimuli (nerve stimulation, carbachol, and forskolin). Longitudinal smooth muscle displayed altered spontaneous contractile activity, length-tension relationships, and carbachol-stimulated contraction in tissues excised from mice 20 and 40 h posttreatment. Anti-CD3 treatment did not affect stimulated ACh release from myenteric plexus neurons. We conclude that specific T cell activation via anti-CD3 antibody results in dramatic alterations in jejunal epithelial and smooth muscle function. Such T cell-induced changes in intestinal function may contribute to the symptomatology of T cell-mediated enteropathies, including graft-versus-host disease, celiac disease, and idiopathic inflammatory bowel disease.


Asunto(s)
Anticuerpos/farmacología , Complejo CD3/inmunología , Yeyuno/efectos de los fármacos , Yeyuno/fisiopatología , Activación de Linfocitos/fisiología , Linfocitos T/efectos de los fármacos , Linfocitos T/fisiología , Acetilcolina/metabolismo , Animales , Bromodesoxiuridina/metabolismo , Cricetinae , Femenino , Técnicas In Vitro , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/inervación , Mucosa Intestinal/patología , Mucosa Intestinal/fisiopatología , Yeyuno/inervación , Yeyuno/patología , Linfocitos/metabolismo , Ratones , Ratones Endogámicos BALB C , Músculo Liso/fisiopatología , Neuronas/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis
12.
Dtsch Med Wochenschr ; 124(3): 39-44, 1999 Jan 22.
Artículo en Alemán | MEDLINE | ID: mdl-9987484

RESUMEN

HISTORY AND ADMISSION FINDINGS: A 63-year-old man had for 10 months suffered from marked weight loss, night sweats, diffuse abdominal pain and increased stool frequency. He was admitted to evaluate an ultrasonically abnormal focus in the liver parenchyma and elevated liver function parameters. His sclerae were obviously icteric and he looked under-weight. INVESTIGATIONS: He had a hypochromic microcytic anemia and abnormal liver and pancreatic function tests: total bilirubin 3.11 mg/dl, direct bilirubin 2.21 mg/dl, GOT21U/l, gamma-GT 422 U/l, alkaline phosphatase 1449 U/l, alpha-amylase 481 U/l, lipase 2827 U/l. The serum creatinine level was elevated to 1.47 mg/dl. Computed tomography revealed enlarged liver and spleen as well as an enlargement of intraabdominal lymph nodes, chest radiogram and endoscopic cholangio-pancreatography were unremarkable. Biopsies from the lower duodenum, large intestine, bone marrow and liver showed inflammatory changes with Langhans-type mononuclear granulomas. Together with these findings an increased activity of the angiotensin-converting-enzyme (ACE) indicated sarcoidosis, other causes having been excluded. TREATMENT AND COURSE: All signs and symptoms rapidly improved under prednisolone, and 4 weeks after begin of treatment the biochemical abnormalities had clearly regressed. The raised serum levels of soluble IL-2 receptors and of neopterin, measures of sarcoidosis activity, had decreased. Activity of ACE had fallen. CONCLUSION: Sarcoidosis can present with diverse clinical signs and symptoms. In a case of multi-system disease that cannot be readily classified, sarcoidosis should be included in the differential diagnosis.


Asunto(s)
Enfermedades Gastrointestinales/diagnóstico , Sarcoidosis/diagnóstico , Antiinflamatorios/administración & dosificación , Antiinflamatorios/uso terapéutico , Biopsia , Médula Ósea/patología , Diagnóstico Diferencial , Duodeno/patología , Estudios de Seguimiento , Enfermedades Gastrointestinales/tratamiento farmacológico , Enfermedades Gastrointestinales/patología , Humanos , Intestino Grueso/patología , Hígado/patología , Hepatopatías/diagnóstico , Masculino , Persona de Mediana Edad , Prednisolona/administración & dosificación , Prednisolona/uso terapéutico , Sarcoidosis/tratamiento farmacológico , Sarcoidosis/patología , Factores de Tiempo
13.
Semin Immunol ; 10(1): 69-78, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9529657

RESUMEN

In chronic inflammatory bowel disease, self-destructive, exaggerated inflammation seems to occur in the absence of a well defined pathogen. However, epidemiological data strongly suggests that development of disease does not depend on endogenous factors alone. In this review, we summarize how a possible role for microbial factors can be reconciled with the current understanding of etiology and pathogenesis of IBD. The data presented does not support that IBD is an infectious disease nor that it is a self-antigen-specific autoimmune disease, however, recent findings increasingly suggest that tissue damage might be caused by a non-specific autoaggressive inflammation which is driven by common, ubiquitous microbial agents derived from the bacterial flora in the intestinal lumen.


Asunto(s)
Enfermedades Inflamatorias del Intestino/microbiología , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/microbiología , Enfermedades Autoinmunes/fisiopatología , Infecciones Bacterianas/inmunología , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/fisiopatología , Causalidad , Enfermedad Crónica , Ambiente , Humanos , Inflamación , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/fisiopatología
14.
J Immunol Methods ; 202(1): 1-11, 1997 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-9075766

RESUMEN

Mucosal macrophages play a fundamental role in the regulation of immunological events and inflammation in the small intestine. Because no information is available on normal small intestinal macrophages, we developed a technique for the isolation and purification of jejunal lamina propria macrophages in order to study their phenotype and activity. From sections of normal human jejunum, lamina propria mononuclear cells were isolated by neutral protease digestion and then subjected to counterflow centrifugal elutriation to purify the macrophages. The cells isolated by this procedure contained < 1% CD3+ lymphocytes and displayed the size distribution, morphological features, ultrastructure and phagocytic activity of mononuclear phagocytes. In contrast to blood monocytes, however, mucosal macrophages from the jejunum did not exhibit adherence properties or express CD14, a receptor for the lipopolysaccharide-binding protein. The purification of large numbers of lamina propria macrophages by this procedure offers the opportunity to define the role of this cell in the physiological inflammation characteristic of normal intestinal mucosa and the pathological inflammation associated with small intestinal diseases.


Asunto(s)
Separación Celular/métodos , Mucosa Intestinal/citología , Mucosa Intestinal/inmunología , Yeyuno/citología , Yeyuno/inmunología , Receptores de Lipopolisacáridos/análisis , Macrófagos/inmunología , Centrifugación , Citometría de Flujo , Humanos
15.
Naunyn Schmiedebergs Arch Pharmacol ; 347(2): 137-40, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8474534

RESUMEN

The effects of agonists and antagonists of 5-hydroxytryptamine (5-HT) receptors on the release of endogenous 5-HT from enterochromaffin cells were studied in the vascularly perfused isolated guinea-pig small intestine. The experiments were done in the presence of tetrodotoxin in order to exclude a neuronally mediated influence on 5-HT release. The 5-HT3 receptor agonist 2-methyl-5-HT increased 5-HT release, and this effect was antagonized by 1 nmol/l tropisetron. Nanomolar concentrations of tropisetron, MDL 72,222 and granisetron decreased 5-HT release. Ondansetron (0.1 and 1 mumol/l) did not modify 5-HT release. 5-Methoxytryptamine, BIMU8 and cisapride concentration-dependently inhibited 5-HT release. BIMU8 was more potent than 5-methoxytryptamine. Micromolar concentrations of tropisetron (1 and 10 mumol/l) enhanced the release, whilst methiothepine (0.1 mumol/l) did not affect the release of 5-HT. The results suggest that enterochromaffin cells of the guinea-pig ileum do not contain 5-HT1 and 5-HT2 receptors, but are endowed with 5-HT3 and 5-HT4 autoreceptors. Activation of the 5-HT3 receptors triggers a positive feedback mechanism leading to an increase of 5-HT release. The 5-HT3 receptors on the enterochromaffin cell differ from neuronal 5-HT3 receptors on guinea-pig myenteric plexus by their high affinity for tropisetron and MDL 72,222, and their very low affinity for ondansetron. Stimulation of 5-HT4 receptors causes inhibition of release; the inhibitory 5-HT4 receptor mechanism appears to predominate.


Asunto(s)
Intestino Delgado/metabolismo , Receptores de Serotonina/fisiología , Serotonina/metabolismo , Animales , Células Enterocromafines/efectos de los fármacos , Células Enterocromafines/metabolismo , Células Enterocromafines/ultraestructura , Femenino , Cobayas , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/ultraestructura , Intestino Delgado/efectos de los fármacos , Intestino Delgado/ultraestructura , Masculino , Perfusión , Receptores de Serotonina/clasificación , Antagonistas de la Serotonina/farmacología , Agonistas de Receptores de Serotonina/farmacología , Tetrodotoxina/farmacología
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