Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
Rev. bras. enferm ; 67(5): 708-714, Sep-Oct/2014. tab
Artigo em Português | LILACS, BDENF | ID: lil-731213

RESUMO

Pesquisa descritiva, qualitativa, que objetivou conhecer como os profissionais de atenção pré-hospitalar percebem as intervenções nas pessoas em crise psíquica. O estudo foi realizado, no estado de Santa Catarina, com quatro equipes das Unidades de Suporte Básico do Serviço de Atendimento Móvel de Urgência, mediante entrevista, no período de abril a junho de 2011. Utilizou-se como método de análise o Discurso do Sujeito Coletivo. Dos resultados emergiram dois temas: Percepção das dificuldades no atendimento à pessoa em crise psíquica e Sugestões na busca por um atendimento mais próximo do desejado à pessoa em crise psíquica. As dificuldades apontadas se relacionam à falta de capacitação e de um local para encaminhamento e sugerem treinamento e sistematização do atendimento. Conclui-se que se faz necessário investir em processo de formação pautado em novas estratégias de cuidado norteadas pelos princípios do SUS e no paradigma psicossocial, além de rediscutir a estratégia de protocolos como sistemas norteadores e não padronizadores.


A qualitative and descriptive research, aimed at knowing how the pre-hospital care professionals perceive the interventions towards people in mental crisis. The study was developed in Santa Catarina with four teams of basic life support units of the Department of Mobile Emergency Care, during April to June 2011. The Collective Subject Discourse was used as the method of analysis. Two themes emerged: Awareness of the difficulties in meeting a person in mental crisis and Suggestions in the search for a closer attention to the person in mental crisis. The difficulties mentioned were related to the lack of training and a local to forward the patients, suggesting a better training and systematization of care. We conclude that it is necessary to invest in the educational process, based on new care strategies guided by the principles of SUS and of the psychosocial paradigm, and revisit the strategy of protocols as guidelines and not as standardizing systems.


Investigación descriptivo-cualitativa, que objetivó conocer como los profesionales de la atención pre-hospitalaria perciben las intervenciones en personas con crisis mental. El estudió fue realizado en Santa Catarina con cuatro equipos de las Unidades de Soporte Vital Básico, mediante entrevista realizada de abril a junio de 2011. El Discurso del Sujeto Colectivo fue utilizado como método de análisis; surgiendo dos temas: Percepción de las dificultades en la atención a la persona en crisis mental y Sugerencias en la búsqueda de una mejor atención a la persona en crisis mental. Las dificultades mencionadas se relacionan con la falta de capacitación y lugar para la atención, sugiriendo un mejor entrenamiento y sistematización de la atención. Se resalta la necesidad de invertir en el proceso de formación basado en nuevas estrategias de atención guiadas por los principios del SUS y el paradigma psicosocial, y revisar la estrategia de protocolos como nortes no estandarizados.


Assuntos
Animais , Masculino , Ratos , Medicamentos de Ervas Chinesas/farmacologia , Ácido Oleanólico/análogos & derivados , Pâncreas/efeitos dos fármacos , Saponinas , Sapogeninas/farmacologia , Amilases , Cálcio/metabolismo , Técnicas In Vitro , Pâncreas/citologia , Pâncreas/metabolismo , Ratos Wistar , Sincalida
2.
Int. j. morphol ; 31(4): 1421-1429, Dec. 2013. ilus
Artigo em Espanhol | LILACS | ID: lil-702328

RESUMO

Debido al auge de la medicina regenerativa, las Células Madre (SC) representan una fuente de reemplazo celular para cualquier tejido, decidiendo emprender este trabajo de investigación con el objetivo de diferenciar células madre embrionarias de ratón (mESC) a células pancreáticas tempranas, realizando su caracterización génica y morfológica. Primeramente se cultivaron y arrestaron en su ciclo celular fibroblastos embrionarios de ratón (MEF) con mitomicina, posteriormente se expandieron las mESC y se sometieron a un protocolo de diferenciación de 21 días hacía células pancreáticas tempranas, evaluándose durante la diferenciación su morfología y expresión relativa de los genes sox-17, pdx-1, ins-1 e ins-2, determinando además la producción de las proteínas insulina y glucagón mediante inmunocitoquímica y citometría de flujo. Se obtuvieron cuerpos embrionarios (EBs) a partir de mESC, con características morfológicas diferentes de acuerdo a su diferenciación, los cuales expresaron genes de la línea germinal endodérmica (sox-17 y pdx-1) a los días 0, 11 y 17 de diferenciación, gen inductor del desarrollo embrionario pancreático (pdx-1) al día 11 de diferenciación y, genes de expresión pancreática (ins-1 e ins-2) a los días 17 y 21 de diferenciación. Finalmente se detectó la producción de proteínas insulina y glucagón en los EBs al día 21 de diferenciación. Se logró diferenciar mESC. El análisis morfológico evidenció cúmulos celulares tridimensionales correspondientes a EBs. Con el análisis de los patrones de expresión génica, se distinguieron inicialmente células con características genéticas de endodermo y posteriormente a partir del día 17 células pancreáticas tempranas, las cuales al día 21 de diferenciación expresaron las proteínas insulina y glucagón...


Due to the boom in regenerative medicine, Stem Cells (SC) represent a source of cell replacement to any tissue, we decided to undertake this research with the objective of differentiating mouse embryonic stem cells (mESC) to early pancreatic cells, developing their genetic and morphological characterization. Initially Mouse embryonic fibroblasts (MEF) were grown and arrested in their cell cycle with mitomycin, subsequently mouse embryonic SC (mESC) were expanded and subjected in to a pancreatic cell differentiation protocol of 21 days. During differentiation, morphology and the relative expression of sox-17, pdx-1, Ins-1 and Ins-2 genes were assessed, also the production of insulin and glucagon proteins was determinated by fluorescence microscopy and flow cytometry. Embryoid bodies (EBs) were obtained from mESC, with different morphological characteristics according to their differentiation, which expressed endodermal germ line genes (sox-17 y pdx-1) at days 0, 11 and 17 of differentiation, an inductor gene of embryonic pancreas development (pdx-1) was detected at day 11 of differentiation. Pancreas genes (ins-1 e ins-2) were expressed at day 17 and 21 of differentiation. Finally the production of insulin and glucagon proteins was detected on the EBS at day 21 of differentiation. In conclusion, the mESC differentiation was achieved. The morphological analysis evidenced three-dimensional cell clusters corresponding to EBs. Analysis of the gene expression patterns in the differentiation process, cells initially showed genetic characteristics of endoderm and thereafter from day 17 of differentiation characteristics of early pancreatic cells which by day 21 of differentiation expressed insulin and glucagon proteins...


Assuntos
Animais , Camundongos , Diferenciação Celular , Células-Tronco Embrionárias/fisiologia , Células Secretoras de Insulina/fisiologia , Citometria de Fluxo , Imuno-Histoquímica , Insulina/biossíntese , Pâncreas/citologia , Reação em Cadeia da Polimerase em Tempo Real
3.
Pakistan Journal of Medical Sciences. 2013; 29 (3): 809-813
em Inglês | IMEMR | ID: emr-127345

RESUMO

This study is to investigate the relationship between 25-Hydroxyvitamin D [25-OH-D] and pancreatic islet beta cell function under different glucose tolerance statuses in China. Totally, 180 patients with type 2 diabetes mellitus [DM group], 178 patients with impaired fasting glucose/impaired glucose tolerance [IFG/IGT group], and 160 normal control subjects [NGT group] were included to measure their body parameters and biochemical parameters. In oral glucose tolerance test, fasting serum 25-OH-D was assessed by the enzyme-linked immunosorbent assay [ELISA]. Homeostasis model assessment for insulin resistance [Homa-IR], insulin acuity index [IAI], beta -cell function index [Homa-BCF] as well as secretion index [IS] were determined. The levels of 25-OH-D, IAI and Homa-BCF in the DM group and IFG/IGT group were significantly lower than that in NGT group [P < 0.05]. Homa-IR in DM group and IFG/IGT group was significantly higher than that in the NGT group [P < 0.05]. Pearson correlation analysis and partial correlation analysis showed that 25-OH-D was positively correlated with fasting insulin [FINS] and Homa-BCF [P < 0.05]. Multiple stepwise regression analysis showed that 25-OH-D was one of the influential factors of pancreatic islet beta cell function in patients with type 2 diabetes mellitus. Our results suggest that 25-OH-D is closely related with the function of the pancreatic islet beta cells and is one of the influential factors of pancreatic islet beta cell function


Assuntos
Humanos , Feminino , Masculino , Ilhotas Pancreáticas/fisiologia , Diabetes Mellitus Tipo 2 , Pâncreas/citologia , Diabetes Mellitus , Insulina
4.
Experimental & Molecular Medicine ; : 653-659, 2011.
Artigo em Inglês | WPRIM | ID: wpr-73121

RESUMO

In an oxygen-depleted environment, endothelial cells initiate an adaptive pattern of synthesis, which may enable them to survive hypoxic crises. Using high-resolution two-dimensional gel electrophoresis in conjunction with mass spectroscopy, we obtained a 24 differential display of proteins in the pancreatic endothelial cell line, MS-1, at four time points following induction of hypoxia. The induction of Wee1 under hypoxia was confirmed both at the mRNA and protein levels. The phosphorylation of cell division cycle 2, which is downstream of Wee1, was also increased after hypoxic exposure. In addition, pre-exposure to hypoxia attenuated a decrease in hydrogen peroxide-induced cell number. The induction of bax (a pro-apoptotic protein) and reduction of bcl (an anti-apoptotic protein) after hypoxia stimulus were also attenuated by hypoxic pre-exposure. Moreover, hydrogen peroxide-induced morphologic damage did not appear in the wild-type Wee1-expressing cells. Taken together, our results suggest that Wee1 may have important role in hypoxia-induced pathophysiological situations in endothelial cells.


Assuntos
Animais , Camundongos , Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular/genética , Hipóxia Celular , Linhagem Celular , Sobrevivência Celular , Células Endoteliais/citologia , Regulação da Expressão Gênica , Peróxido de Hidrogênio/metabolismo , Proteínas Nucleares/genética , Pâncreas/citologia , Fosforilação , Proteínas Tirosina Quinases/genética
5.
Rio de Janeiro; s.n; 2010. 92 p. ilus.
Tese em Português | LILACS | ID: lil-590534

RESUMO

Estudos populacionais, assim como modelos animais demonstram que além dos fatores já conhecidos, como uma dieta não balanceada e sedentarismo, insultos nutricionais no período gestacional ou durante a lactação, causam alterações metabólicas importantes que levam ao surgimento da obesidade, Diabetes Mellitus tipo 2 (DM2) e doenças cardiovasculares em longo prazo. Nesse estudo, analisamos o pâncreas de camundongos hiperalimentados adultos (150 dias) e camundongos hiperaliemntados jovens (21 e 28 dias). Os camundongos hiperalimentados de 21 dias receberam transplante de células mononucleares de medula óssea (CMO) e o resultado desse transplante foi observado aos 28 dias, quando os animais foram sacrificados. Nós investigamos: a apoptose das células beta através do fator pró-apoptótico Bax; a proliferação das células da ilhota pancreática através do antígeno nuclear de proliferação celular (PCNA); a expressão da citocina TNF-alpha, relacionado com a resistência à insulina em animais obesos e a expressão de células tronco CD133 com o objetivo de estudar a participação dessa célula na renovação da massa de células beta durante o estabelecimento da DM2. As análises das proteínas citadas no pâncreas foram realizadas através de microscopia de luz, microscopia confocal, microscopia eletrônica e Western blotting. O peso dos animais, a morfometria das ilhotas pancreáticas, bem como os níveis de glicose e insulina plasmáticos também foram determinados. Nossos resultados confirmaram que os camundongos hiperalimentados adultos apresentavam elevados níveis de glicose e insulina plasmática quando comparados ao grupo controle. Além disso, camundongos hiperalimentados adultos apresentaram aumento na expressão de Bax, indicando apoptose das células beta, maior expressão de TNF-alpha nas ilhotas pancreáticas, e presença de células CD133 nas ilhotas e ductos pancreáticos de camundongos hiperalimentados. Ao analisarmos os animais com 21 dias também observamos elevados níveis...


Population studies as well as animal models show that besides the factors already known as an unbalanced diet and sedentary lifestyle, nutritional insults during pregnancy of during lactation, causes important metabolic changes that lead to the emergence of obesity, type 2 diabetes mellitus (DM2) and cardiovascular diseases in long-term. In this study, we analyzed the pancreas of overfed adult mice (150 days) and young mice (21 and 28 days). At day 21, overfed mice were transplanted with bone marrow mononuclear cells (BMCs) and the results of this transplantation were observed at day 28. We investigated beta-cell apoptosis through pro-apoptotic factor Bax, the proliferation of pancreatic islet cells by proliferating cell nuclear antigen (PCNA), expression of TNF-alpha which has been linked to insulin resistance in obese animals and the expression of CD133 stem cells, in order to study the participation of this cell on the recovery of beta-cell mass during the establishment of DM2. The protein analysis, were performed using light microscopy, confocal microscopy, electron microscopy and Western blotting. The animals weight, morphology of pancreatic islets, as well as plasma levels of glucose and insulin were also determined. Our results confirmed that adult overfed mice had high levels of blood glucose and insulin when compared to control mice. Moreover, overfed adult mice showed an increased expression of Bax, indicating apoptosis of beta cells, also confirmed by transmission electron microscopy, increased expression of TNF-alpha in pancreatic islets when compared with the control group, and interestingly we observed the presence of CD133 cells in the pancreas of overfed mice. By analyzing the animals with 21 days, we also observed high levels of blood glucose and insulin in the overfed group, but we did not observe Bax expression at this lifetime. The expression of TNF-alpha was also increased in pancreas of overfed mice at day 21...


Assuntos
Animais , Camundongos , Antígenos CD/metabolismo , Transplante de Medula Óssea , Células-Tronco/citologia , Células-Tronco/fisiologia , Fator de Necrose Tumoral alfa/análise , Hiperfagia/metabolismo , Ilhotas Pancreáticas/citologia , Pâncreas/citologia , Pâncreas/metabolismo , Resistência à Insulina/fisiologia , Lactação/metabolismo
6.
JCPSP-Journal of the College of Physicians and Surgeons Pakistan. 2008; 18 (9): 578-580
em Inglês | IMEMR | ID: emr-102970

RESUMO

The solid-cystic pseudopapillary neoplasm is a rare pancreatic tumor having indolent course and amenable to complete excision. This is a report of two cases of this tumour, diagnosed on fine needle aspiration cytology. One of the cases had complete surgical excision of the mass and subsequent histological evaluation. This benign and rare neoplasm of pancreas often causes few symptoms. The characteristic cytomorphological features point towards the diagnosis


Assuntos
Humanos , Feminino , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/diagnóstico por imagem , Biópsia por Agulha Fina , Dor Abdominal , Testes de Função Hepática , Imuno-Histoquímica , Pâncreas/citologia
7.
Braz. j. biol ; 67(4): 735-740, Nov. 2007. ilus
Artigo em Inglês | LILACS | ID: lil-474199

RESUMO

In the present study, we investigated types of pancreatic endocrine cells and its respective peptides in the Brazilian sparrow species using immunocytochemistry. The use of polyclonal specific antisera for somatostatin, glucagon, avian pancreatic polypeptide (APP), YY polypeptide (PYY) and insulin, revealed a diversified distribution in the pancreas. All these types of immunoreactive cells were observed in the pancreas with different amounts. Insulin- Immunoreactive cells to (B cells) were most numerous, preferably occupying the central place in the pancreatic islets. Somatostatin, PPA, PYY and glucagon immunoreactive cells occurred in a lower frequency in the periphery of pancreatic islets.


Os tipos de células endócrinas e seus respectivos peptídeos reguladores foram estudados imunocitoquimicamente no pâncreas do tico-tico, espécie Zonotrichia capensis subtorquata, empregando-se o método imunocitoquímico ABC - Peroxidase (Complexo Avidina - Biotina - Peroxidase) e anti-soros específicos para somatostatina, ao glucagon, ao polipeptídeo pancreático aviário (PPA), ao polipeptídeo YY (PYY) e à insulina. Todos estes tipos de células imunorreativas foram observadas no pâncreas em quantidades diferentes. As células imunorreativas à insulina (células B) foram as mais numerosas, ocupando preferencialmente, a região central das ilhotas pancreáticas. As células endócrinas imunorreativas à somatostatina, PPA, PYY e glucagon localizaram-se predominantemente na periferia das ilhotas.


Assuntos
Animais , Pâncreas/metabolismo , Pardais/metabolismo , Brasil , Glucagon/metabolismo , Imuno-Histoquímica/veterinária , Insulina/metabolismo , Pâncreas/citologia , Polipeptídeo Pancreático/metabolismo , Peptídeo YY/metabolismo , Somatostatina/metabolismo
8.
Yonsei Medical Journal ; : 526-530, 2007.
Artigo em Inglês | WPRIM | ID: wpr-71485

RESUMO

PURPOSE: In non-excitable cells, which include parotid and pancreatic acinar cells, Ca(2+) entry is triggered via a mechanism known as capacitative Ca(2+) entry, or store-operated Ca(2+) entry. This process is initiated by the perception of the filling state of endoplasmic reticulum (ER) and the depletion of internal Ca(2+) stores, which acts as an important factor triggering Ca(2+) entry. However, both the mechanism of store-mediated Ca(2+) entry and the molecular identity of store-operated Ca(2+) channel (SOCC) remain uncertain. MATERIALS AND METHODS: In the present study we investigated the Ca(2+) entry initiation site evoked by depletion of ER to identify the localization of SOCC in mouse parotid and pancreatic acinar cells with microfluorometeric imaging system. RESULTS: Treatment with thapsigargin (Tg), an inhibitor of sarco/endoplasmic reticulum Ca(2+)-ATPase, in an extracellular Ca(2+) free state, and subsequent exposure to a high external calcium state evoked Ca(2+) entry, while treatment with lanthanum, a non-specific blocker of plasma Ca(2+) channel, completely blocked Tg-induced Ca(2+) entry. Microfluorometric imaging showed that Tg-induced Ca(2+) entry started at a basal membrane, not a apical membrane. CONCLUSION: These results suggest that Ca2+ entry by depletion of the ER initiates at the basal pole in polarized exocrine cells and may help to characterize the nature of SOCC.


Assuntos
Animais , Camundongos , Cálcio/metabolismo , Canais de Cálcio/efeitos dos fármacos , Células Cultivadas , Retículo Endoplasmático/efeitos dos fármacos , Camundongos Endogâmicos ICR , Microscopia de Fluorescência , Pâncreas/citologia , Glândula Parótida/citologia , Tapsigargina/farmacologia
9.
Radiol. bras ; 38(6): 451-458, nov.-dez. 2005. ilus, tab
Artigo em Português | LILACS | ID: lil-421251

RESUMO

O diagnóstico das lesões císticas pancreáticas pelos métodos de imagem, especialmente as de pequeno tamanho, é cada vez mais freqüente. Em alguns casos, ele representa um dilema em relação à terapêutica, podendo ser pseudocistos inflamatórios, neoplasias primárias ou secundárias. Para a decisão terapêutica, é necessário definir se a neoplasia é benigna, maligna ou potencialmente maligna. Hoje, a ecoendoscopia é considerada o exame padrão-ouro para a investigação do pâncreas, fornecendo dados sobre a morfologia destas lesões e possibilitando, por meio da punção guiada em tempo real, a colheita de material para avaliação citológica e dos marcadores tumorais. Este procedimento é considerado seguro e eficiente e apresenta taxas de sensibilidade e especificidade altas e de morbidade e de complicações baixas. No diagnóstico das lesões mucinosas do pâncreas, os fatores preditivos mais significativos para o diagnóstico diferencial são a presença de septos, os nódulos murais e as alterações parenquimatosas, para o qual as taxas de sensibilidade, especificidade e grau de exatidão são, respectivamente, 94 por cento, 85 por cento e 88 por cento. Os autores têm por objetivo revisar as principais neoplasias císticas primárias do pâncreas, enfatizando a aplicação da ecoendoscopia no diagnóstico definitivo dessas neoplasias.


Pancreatic cystic lesions, particularly small lesions, are more easily diagnosed nowadays with the use of imaging methods. In some cases, the diagnosis represents a challenge to establish the treatment, as it can range from inflammatory pseudocysts to primary or metastatic cystic neoplasms. In order to choose the treatment, it is necessary to determine if the lesion is benign, borderline, or malignant. Currently, echoendoscopy is considered the gold standard procedure for pancreatic evaluation as it clearly shows the morphology of the lesion, and also allows the acquisition of pancreatic material for cytological and tumor markers studies using fine needle aspiration biopsy. This procedure is considered safe and efficient with high rates of sensibility and specificity and low rates of complications and morbidity. The presence of septa, mural nodules and irregularities in the parenchyma are the most significant predictive factors for the differential diagnosis of mucinous pancreatic-cystic lesions for which sensibility, specificity and accuracy rates are 94%, 85% and 88%, respectively. The aim of the authors in this study is to review the major primary-cystic-pancreatic neoplasms with emphasis in the application of echoendoscopy for the definite diagnosis of these lesions.


Assuntos
Humanos , Técnicas e Procedimentos Diagnósticos , Neoplasias Císticas, Mucinosas e Serosas , Neoplasias Císticas, Mucinosas e Serosas/etiologia , Neoplasias Pancreáticas , Pâncreas/citologia , Pâncreas/fisiopatologia , Endossonografia , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/diagnóstico
10.
Artigo em Inglês | IMSEAR | ID: sea-65379

RESUMO

OBJECTIVE: Pancreatic stellate cells (PSC) are considered as the principal effector cells in pancreatic fibrosis. We studied the role of platelet-derived growth factor (PDGF) in the activation of PSC. METHODS: Cultured rat PSC were co-incubated with PDGF-BB (25 ng/mL) and different doses (0-40 ng/mL) of PD98059, a specific inhibitor of extracellular signal-regulated kinase (ERK). Expressions of p ERK1 protein and of collagen a1(I) mRNA were measured. RESULTS: Expression of p ERK1 protein was up-regulated by PDGF-BB, and was down-regulated in a dose-dependent manner by PD98059. Expression of collagen a1(I) mRNA also showed an increase with PDGF-BB and non-dose-dependent inhibition by PD98059. CONCLUSION: Our findings suggest that PSC activation is mediated by PDGF signal pathway, and ERK1 protein plays an important role in this activation.


Assuntos
Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Colágeno Tipo I/antagonistas & inibidores , Flavonoides/farmacologia , Masculino , Pâncreas/citologia , Fator de Crescimento Derivado de Plaquetas/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , eIF-2 Quinase/antagonistas & inibidores
11.
Biocell ; 28(2): 127-134, ago. 2004. ilus, tab
Artigo em Inglês | LILACS | ID: lil-403132

RESUMO

Although the endocrine pancreas is the purpose of several deep investigations, morphological data referred to the effect of aging on the gland are not homogeneous. The purpose of the current work was to analyze the changes occurring in the pancreas of aged rats, with especial reference to the islet cell populations. Six young (Y), old (O) and senescent (S) male Sprague-Dawley rats were used. The pancreas tails were processed for light microscopy and studied by means of routine stains as well as by immunohistochemical identification of insulin-, glucagon-, somatostatin-, and pancreatic polypeptide- secreting cells (Dako Envision System, DAB as chromogen). A progressive pancreatic histoarchitecture distortion was found among the aged animals. Even when the alterations were not uniformly observed, they appeared more evident and severe in the S group. The S rats showed significantly increased volume density and cell density of the B cell population, as well as larger number of islet profiles, when compared to O rats. A significant progressive increment of adipose tissue was also evident in aged animals. No abnormal changes were detected in the non.B cell populations of the different groups.


Assuntos
Masculino , Animais , Ratos , Envelhecimento/fisiologia , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/fisiologia , Pâncreas/citologia , Pâncreas/fisiologia , Imuno-Histoquímica , Ratos Sprague-Dawley
12.
Biol. Res ; 37(4): 593-602, 2004. graf
Artigo em Inglês | LILACS | ID: lil-437513

RESUMO

Calcium release via intracellular Ca2+ release channels is a central event underpinning the generation of numerous, often divergent physiological processes. In electrically non-excitable cells, this Ca2+ release is brought about primarily through activation of inositol 1,4,5-trisphosphate receptors and typically takes the form of calcium oscillations. It is widely believed that information is carried in the temporal and spatial characteristics of these signals. Furthermore, stimulation of individual cells with different agonists can generate Ca2+ oscillations with dramatically different spatial and temporal characteristics. Thus, mechanisms must exist for the acute regulation of Ca2+ release such that agonist-specific Ca2+ signals can be generated. One such mechanism by which Ca2+ signals can be modulated is through simultaneous activation of multiple second messenger pathways. For example, activation of both the InsP3 and cAMP pathways leads to the modulation of Ca2+ release through protein kinase A mediated phosphoregulation of the InsP3R. Indeed, each InsP3R subtype is a potential substrate for PKA, although the functional consequences of this phosphorylation are not clear. This review will focus on recent advances in our understanding of phosphoregulation of InsP3R, as well as the functional consequences of this modulation in terms of eliciting specific cellular events.


Assuntos
Animais , Canais de Cálcio/metabolismo , Citosol/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Sinalização do Cálcio , Sinalização do Cálcio/fisiologia , Técnicas de Cultura de Células , Glândula Parótida , Glândula Parótida/fisiologia , Fosforilação , Pâncreas/citologia , Pâncreas
13.
Biol. Res ; 37(4): 661-664, 2004.
Artigo em Inglês | LILACS | ID: lil-437523

RESUMO

The pancreatic acinar unit is a classical example of a polarized tissue. Even in isolation, these cells retain their polarity, and this has made them particularly useful for Ca2+ signaling studies. In 1990, we discovered that this cell has the capability of producing both local cytosolic and global Ca2+ signals. The mechanisms underlying this signal generation have now been established. Furthermore, it has become clear that the local signals are sufficient for the control of both fluid and enzyme secretion, whereas prolonged global signals are dangerous and give rise to acute pancreatitis, a disease where the pancreas digests itself.


Assuntos
Humanos , Comunicação Celular/fisiologia , Polaridade Celular/fisiologia , Sinalização do Cálcio/fisiologia , /fisiologia , Pâncreas/citologia , Pâncreas/fisiologia , Pancreatite/fisiopatologia , Potenciais da Membrana/fisiologia
14.
The Korean Journal of Gastroenterology ; : 519-526, 2003.
Artigo em Coreano | WPRIM | ID: wpr-96871

RESUMO

BACKGROUND/AIMS: Pancreatic acini of streptozotocin (STZ)-induced diabetic rats release amylase less than normal acini on cholecystokinin (CCK) stimulation. Pancreatic enzyme secretion has been closely related to the intracellular calcium concentration ([Ca2+]i) of the acinar cell. In the present study, sequential changes of the intracellular calcium signal which probably underlie the altered enzyme secretion in response to CCK-8 were investigated using pancreatic acini from diabetic rats. METHODS: Diabetic rats were prepared by single intravenous injection of STZ (70 mg/kg). Stimulating experiments with CCK-8 were performed 7 days later. Pancreatic acini were isolated by collagenase digestion. Amylase release and [Ca2+]i were measured by colorimethod and calcium imaging, respectively. The geometry of intracellular calcium signal was analyzed. RESULTS: Normal acini exhibited concentration-dependent [Ca2+]i increase and regular oscillatory calcium signal on CCK-8 stimulation. Amylase release was also concentration-dependent. However, diabetic acini showed significantly less [Ca2+]i increase, prolonged time to peak [Ca2+]i, decreased calcium spikes number, and decreased amylase release compared with normal acini. The decreased [Ca2+]i in diabetic acini was restored significantly by insulin treatment. CONCLUSIONS: Relatively decreased amylase release in diabetic pancreatic acini in response to CCK, appears to be associated with altered calcium signal due to insulin deficiency.


Assuntos
Animais , Ratos , Amilases/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Diabetes Mellitus Experimental/fisiopatologia , Pâncreas/citologia , Ratos Sprague-Dawley , Sincalida/farmacologia
15.
Experimental & Molecular Medicine ; : 379-384, 2003.
Artigo em Inglês | WPRIM | ID: wpr-171363

RESUMO

Dexamethasone converts pluripotent pancreatic AR42J cells into exocrine cells expressing digestive enzymes. In order to address molecular mechanism of this differentiation, we have investigated the role of mitogen-activated protein (MAP) kinase pathway and gene expressions of p21(waf1/cip1)and nuclear oncogenes (c-fos and c-myc) during AR42J cell differentiation. Dexamethasone markedly increased the intracellular and secreted amylase contents as well as its mRNA level. However, cell growth and DNA content were significantly decreased. With these phenotypic changes, AR42J cells induced transient mRNA expression of p21(waf1/cip1)gene, which reached maximal level by 6 h and then declined gradually toward basal state. In contrast to p21(waf1/cip1), c-fos gene expression was transiently inhibited by 6 h and then recovered to basal level by 24 h. Increased c-myc expression detected after 3 h, peaked by 12 h, and remained elevated during the rest of observation. Dexamethasone inhibited epidermal growth factor-induced phosphorylation of extracellular signal regulated kinase. Inhibition of MAP kinase pathway by PD98059 resulted in further elevation of the dexamethasone-induced amylase mRNA and p21(waf1/cip1)gene expression. These results suggest that p21(waf1/cip1)and nuclear oncogenes are involved in dexamethasone-induced differentiation and inhibition of MAP kinase pathway accelerates the conversion of undifferentiated AR42J cells into amylase-secreting exocrine cells.


Assuntos
Animais , Ratos , Amilases/genética , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ciclinas/genética , Dexametasona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Genes fos/genética , Genes myc/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Pâncreas/citologia , RNA Mensageiro/genética
16.
Journal of Veterinary Science ; : 303-314, 2002.
Artigo em Inglês | WPRIM | ID: wpr-148809

RESUMO

The regional distribution and relative frequency of some endocrine cells in the pancreas of the carp, Cyprinus carpio Linnaeus, belonging to the family Cyprinidae in the order Cypriniformes, were observed using specific mammalian antisera against insulin, glucagon, somatostatin and human pancreatic polypeptide (hPP) by peroxidase antiperoxidase (PAP) method. The pancreas was divided into four regions (principal and secondary islets, exocrine and pancreatic duct regions). In addition, the pancreatic islet regions were further subdivided into three regions (central, mantle and peripheral regions) and the pancreatic duct regions were subdivided into two regions (epithelial and subepithelial regions). Spherical to spindle or occasionally round to oval shaped immunoreactive (IR) cells were demonstrated in the pancreatic islets, exocrine and pancreatic duct. In the principal islet regions, some cells were also detected in the other regions, most of insulin- and somatostatin-IR cells were located in the central regions, and glucagon- and hPP-IR cells were situated in the peripheral regions. In this regions, insulin-IR cells were most predominant cell types and then, glucagon, somatostatin and hPP in that order. In the secondary islet regions, the regional distribution and relative frequency of these four types of endocrine cells were quite similar to those of the principal islets except for cell clusters consisted of hPP-IR cells that were situated in the peripheral to mantle regions. In the pancreatic duct regions, all four major pancreatic endocrine cells were demonstrated in the inter-epithelial cells and/or basal regions of the epithelial linning. In addition, cell clusters composed of numerous insulin-, moderate glucagon- and somatostatin-IR cells of low frequency were also observed in the subepithelial regions of the pancreatic duct. In the exocrine regions, insulin-, glucagon-, somatostatin- and hPP-IR cells were located in the inter-acinus regions with rare, a few, moderate and moderate frequencies, respectively. In conclusion, the regional distribution and relative frequency of four major pancreatic endocrine cells, insulin-, glucagon-, somatostatin- and hPP-IR cells, in the pancreas of the carp showed general patterns which were observed in other stomachless teleost. However, some species- dependent different distributional patterns and/or relative frequencies were also demonstrated.


Assuntos
Animais , Feminino , Masculino , Carpas/metabolismo , Glucagon/metabolismo , Imuno-Histoquímica/veterinária , Insulina/metabolismo , Pâncreas/citologia , Polipeptídeo Pancreático/metabolismo , Somatostatina/metabolismo
17.
Rev. méd. Minas Gerais ; 11(1): 2-6, jan.-mar. 2001. ilus, tab
Artigo em Português | LILACS | ID: lil-585827

RESUMO

Foi verificada a influência da glândula pineal em relação à análise quantitativa das células α, β e δ através de estudo imuno-histoquímico. Vinte ratos Wistar foram distribuídos em 2 grupos (grupo controle - grupo pinealectomizados). Os animais foram sacrificados 70 dias após a cirurgia. Amostras de pâncreas foram coradas com anticorpos monoclonais antiinsulina, antiglucagon e antisomatostatina. Foram contadas as células de cinco ilhotas de cada segmento. O número de células positivas para insulina nos ratos normais variou de 91 a 777 (312,5 ± 203,8) e nos pinealectomizados de 81 a 903 (524,4 ± 300,3); em relação ao glucagon variou nos normais de 83 a 326 (164,6 ± 95,4) e nos pinealectomizados de 95 a 287 (188,8 ± 78,4); em relação à somatostatina variou nos normais de 13 a 65 (35,4 ± 20,9) e nos pinealectomizados de 11 a 65 (29,7 ± 18,4). O número médio de células positivas para insulina nos animais pinealectomizados apresentou-se superior ao dos normais, mas essa superioridade não foi estatisticamente significante (p = 0,08). Estes resultados demonstram que a pineal parece exercer influência no pâncreas endócrino e corroboram estudos prévios.


The influence of the pineal gland on pancreatic islet with respect to a quantitative analysis of α, β and δ cells by immunohistochemistry was verified. Twenty Wistar rats was divided in two groups (control group - pinealectomysed group). The animals were sacrificed 70 days after surgery. Fragments of pancreas segments were stained with anti-insulin, anti-glucagon and antisomatostatin monoclonal antibodies. The cells of five islets were counted in each segments. The number of insulin-positive cells ranged from 91 to 777 (312,5 ± 203,8) in normal rats and from 81to 903 (524,4 ± 300,3) in pinealectomysed rats; glucagon-positive cells ranged from 83 to 326 - 164,6 ± 95,4 - (normals) and from 95 to 287 - 188,8 ± 78,4 - (pinealectomysed); somatostatin-positive cells ranged from 13 to 65 - 35,4 ± 20,9 - (normals) and from 11 to 65 - 29,7 ± 18,4 - (pinealectomysed). The mean number of insulin-positive cells was higher in pinealectomysed animals than in normal animals but not significantly (p = 0.08). These results indicate that the pineal gland seems to have an influence on endocrine pancreas and support previous studies.


Assuntos
Animais , Ratos , Glândula Pineal/cirurgia , Ilhotas Pancreáticas/citologia , Glucagon/química , Insulina/química , Pâncreas/citologia , Ratos Wistar , Somatostatina/química
18.
Journal of Korean Medical Science ; : S44-S45, 2000.
Artigo em Inglês | WPRIM | ID: wpr-117525
19.
Journal of Korean Medical Science ; : S49-S50, 2000.
Artigo em Inglês | WPRIM | ID: wpr-117523
20.
Journal of Korean Medical Science ; : S51-S52, 2000.
Artigo em Inglês | WPRIM | ID: wpr-117522

RESUMO

In pancreatic acinar cells Ca(2+)-dependent secretagogues promote the fusion of zymogen granules (ZG) with the apical plasma membrane (PM) and exocytosis of digestive enzymes. In addition to exocytotic fusion complexes between SNARE proteins in the ZG membrane (ZGM) and the apical PM, enzyme secretion elicited by Ca(2+)-dependent secretagogues requires cytosolic Cl and K+ and is inhibited by blockers of Cl- and K+-channels. We have identified a Cl-conductance activated by ATP, and a K+-conductance (with properties similar to ATP-sensitive K+-channels), regulated by the granule matrix protein Zg-16p in the ZGM. Both conductances are inversely regulated by a 65-kD mdr1 gene product. We have also identified a novel Ca(2+)-activated anion conductance in ZGM, the Ca(2+)-sensitivity of which increases 50-fold when Cl is replaced by 1. This conductance is blocked by micromolar H2-DIDS or DTT, reminiscent of a family of epithelial Ca(2+)-activated Cl -channels (CaCC). Expression of a CaCC in exocrine pancreas has been confirmed by RT-PCR analysis, and by immunoblotting and immunogold labeling of ZG membranes. These data suggest that ion channels in the ZGM are essential elements in pancreatic exocytosis.


Assuntos
Animais , Canais de Cloreto/metabolismo , Canais de Cloreto/genética , Exocitose/fisiologia , Expressão Gênica/fisiologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Pâncreas/metabolismo , Pâncreas/citologia , Canais de Potássio/metabolismo , Canais de Potássio/genética , Vesículas Secretórias/metabolismo , Vesículas Secretórias/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA