Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 102
Filtrar
1.
Urologia ; 78(2): 126-31, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-21574145

RESUMO

Neuroendocrine (NE) cells represent the third epithelial cell type on normal prostatic tissue (in addition to basal and secretory cells). They are localized in all regions of the human prostate at birth but rapidly decrease in the peripheral prostate after birth, and then reappear at puberty. After puberty, their number seems to increase until an apparently optimum level is reached, which persists between the age of 25 and 54. NE cells were defined by Pearse as APUD to refer to chemical characteristics of amine precursor uptake and decarboxylation, common to the cells of this system. The most predominant product of prostatic NE cells is Chromogranin A, but they also produce serotonin, CgB, secretogranin or CgC, thyroid-stimulating hormone-like peptide, calcitonin, katacalcin, PTHrP and a-human chorionic gonadotropin-like peptide. NE cells in normal and neoplastic prostates are devoid of androgen receptors, but they express epidermal growth factor (EGF) receptor and c-erbB-2. For these reason NE cells are androgen-insensitive. The NE component of prostate adenocarcinoma is resistant to hormone therapy; some studies showed that the number of NE tumor cells and CgA serum levels increase with the recovery of human prostate tumor from hormonal therapy. Currently there are no clinical data available to support an active role of radiotherapy in NE differentiation.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Cromogranina A/metabolismo , Células Neuroendócrinas/metabolismo , Tumores Neuroendócrinos/metabolismo , Neoplasias da Próstata/metabolismo , Células APUD/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Antineoplásicos Hormonais/uso terapêutico , Calcitonina/metabolismo , Transformação Celular Neoplásica/efeitos dos fármacos , Gonadotropina Coriônica/metabolismo , Cromogranina B/metabolismo , Cromograninas/metabolismo , Diagnóstico Diferencial , Progressão da Doença , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Células Neuroendócrinas/efeitos dos fármacos , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/patologia , Proteínas Nucleares/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Fragmentos de Peptídeos/metabolismo , Hormônios Peptídicos/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Serotonina/metabolismo , Fatores de Transcrição/metabolismo , Falha de Tratamento
2.
Tissue Cell ; 42(1): 65-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19853267

RESUMO

We used light microscopy to elucidate the morphological features of argyrophilic cells in the digestive tract of the African ostrich (Struthio camelus). The results indicated that argyrophilic cells were found to be distributed among the epithelial cells of the mucosa or glands throughout the digestive tract, except for the esophagus; two types of argyrophilic cells were found; i.e., closed-type cells and cells with triangular or elongated shapes and with their apical cytoplasmic process in contact with the lumen (open-type cells); the greatest number of argyrophilic cells was found in the proventriculus, and the argyrophilic cell density gradually decreased from the proventriculus to the rectum; Furthermore, the number of argyrophilic cells in the duodenum and ileum was higher than that in the jejunum. This text still combined the characteristics that the argyrophilic cells in digestive tract of ostrich maybe related to different digestive function of different region and the basis of their morphology to carry on a discussion. It was speculated that argyrophilic cells in the digestive tract may have both endocrine and exocrine functions.


Assuntos
Células APUD/citologia , Células Epiteliais/citologia , Trato Gastrointestinal/citologia , Mucosa Intestinal/citologia , Sistemas Neurossecretores/citologia , Struthioniformes/anatomia & histologia , Células APUD/metabolismo , Adaptação Fisiológica/fisiologia , Animais , Contagem de Células , Forma Celular/fisiologia , Digestão/fisiologia , Células Epiteliais/fisiologia , Comportamento Alimentar/fisiologia , Feminino , Trato Gastrointestinal/fisiologia , Histocitoquímica , Citometria por Imagem , Mucosa Intestinal/fisiologia , Sistemas Neurossecretores/fisiologia , Coloração pela Prata , Especificidade da Espécie , Struthioniformes/fisiologia
3.
Tidsskr Nor Laegeforen ; 129(15): 1474-7, 2009 Aug 13.
Artigo em Norueguês | MEDLINE | ID: mdl-19690598

RESUMO

BACKGROUND: Neuroendocrine tumours constitute a small group of malignancies; about 200 new patients are diagnosed in Norway annually. This article discusses problems associated with use of deoxyfluoroglucose (FDG) Positron Emission Tomography (PET) and other available options in patients with these conditions, as well as challenges related to introduction of new radiopharmaceutical agents. MATERIAL AND METHODS: The article is based on review of literature in connection with development of new guidelines for nuclear medicine examinations, supplemented with literature identified through a non-systematic search of Pubmed. RESULTS: A large proportion of these tumours grow slowly, and recent data show that 5-year survival is about 50 %. Neuroendocrine tumours are characterised by specific biochemical processes that enable tailoring of radiopharmaceutical agents for PET and consequently a more accurate diagnosis and improved follow-up of these patients. INTERPRETATION: As for other cancer types, diagnostics and detection of metastases are an important factor for correct treatment of neuroendocrine tumours. PET with FDG is of limited use for patients with this condition. New specific radiopharmaceutical agents for PET may imply detection of 90 % of all such tumours.


Assuntos
Tumores Neuroendócrinos/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Células APUD/metabolismo , Controle de Medicamentos e Entorpecentes , Fluordesoxiglucose F18 , Humanos , Tumores Neuroendócrinos/secundário , Noruega , Compostos Radiofarmacêuticos , Receptores de Somatostatina/metabolismo , Sensibilidade e Especificidade
4.
Klin Med (Mosk) ; 86(3): 33-7, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18441701

RESUMO

60 patients with irritable colon syndrome (ICS) were examined. They were divided into 2 groups. Group 1 included 30 patients who had ICS with dominating constipation (ICSc). Group 2 consisted of 30 patients with ICS and dominating diarrhea (ICSd). 12 practically healthy persons composed control group. The patients were being observed in dynamics (in periods of aggravation and remission), under uniform program including clinical, endoscopic, morphologic and immunohistochemical methods. It was established that ICSc development related to hyperplasia and hyperfunction serotonin producing cells together with decrease of number and functional activity of VIP-producing cells and mast cells. It was detected significant increase of colonocytes proliferative activity, shown throw number of immunopositive to cycline Dl epithelial cells, and compensatory increase of apoptosis activity. In patients with ICSd it was registered increase of number and functional activity of general population of apudocytes, serotonin-, melatonin- and VIP-produsing cells and mast cells. It was detected decrease of number of colonocytes immunopositive to cycline D1 and proliferating cell nuclear antigen, and growth of colon epithelial cells apoptosis activity. More significant changes of diffuse endocrine system in patients with ICSd set conditions for progress of changes of cell renovation with frequent colon mucous tunic atrophy, acting as a background for carcinogenesis.


Assuntos
Células APUD/metabolismo , Adipócitos/metabolismo , Ciclina D1/metabolismo , Células Enterocromafins/metabolismo , Síndrome do Intestino Irritável/metabolismo , Síndrome do Intestino Irritável/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Remissão Espontânea
5.
Int Urol Nephrol ; 34(3): 357-60, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12899227

RESUMO

INTRODUCTION: Prostate and seminal vesicles (sv) are both androgen-dependent male sex accessory glands. The cancer incidence in these two organs is vastly different. Neuroendocrine (NE) cells are involved in the regulation of prostate growth, differentiation and in prostate cancer carcinogenesis. Thus, knowledge of the incidence of NE cells in sv may add to our understanding of prostate cancer etiology. METHODS: Samples of histologically confirmed normal prostate tissue and normal sv tissue from 20 men were immunostained for chromogranin A. The incidence of stained cells was evaluated semiquantitately. RESULTS: Neuroendocrine cells were detected in all prostate specimens, but not a single stained cell was found in any of the sv specimens. CONCLUSIONS: The lack of NE cells and, subsequently, of biogenic amines, peptides and growth factors may be a reason for the low cancer incidence in the seminal vesicles. Alternatively, the absence of NE cells can be seen as a hint that the stem cells of the prostate and sv react differently to endogenous and exogenous stimuli, and thus in the seminal vesicles, stem cells are not transformed into NE cells.


Assuntos
Células APUD/metabolismo , Biomarcadores Tumorais/metabolismo , Cromograninas/metabolismo , Próstata/patologia , Neoplasias da Próstata/patologia , Glândulas Seminais/patologia , Cromogranina A , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Glândulas Seminais/metabolismo
6.
Klin Med (Mosk) ; 78(6): 32-5, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10900867

RESUMO

Patients with inflammatory intestinal diseases and colorectal adenocarcinoma in sigmoid mucosa were examined using light and electron microscopy, immunohistochemical tests, radioimmunoassay and morphometry. Functional morphology of the general population of the endocrine cells and apudocytes producing melatonin and serotonin as well as urine excretion of 6-sulfatoxymelatonin changed in quality and quantity. The parameters showed specificity depending on clinicomorphological variant of colorectal pathology. The findings provide additional criteria in diagnosis and prediction of the course of different types of inflammatory and tumor affections of the colon.


Assuntos
Adenocarcinoma/metabolismo , Colite/metabolismo , Neoplasias Colorretais/metabolismo , Mucosa Intestinal/metabolismo , Melatonina/metabolismo , Serotonina/metabolismo , Células APUD/metabolismo , Células APUD/ultraestrutura , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Biomarcadores Tumorais , Biópsia , Colite/patologia , Neoplasias Colorretais/patologia , Progressão da Doença , Feminino , Humanos , Mucosa Intestinal/ultraestrutura , Masculino , Pessoa de Meia-Idade , Prognóstico
7.
Ter Arkh ; 72(2): 32-5, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10717922

RESUMO

AIM: To study functional morphology of a total population of endocrine cells of colon mucosa, mast and enterochromaffine cells. MATERIALS AND METHODS: Light and electrone microscopy, immunohistochemical methods, morphometry were used to study endocrine and mast cells of the sigmoid colon in inflammation. RESULTS: Changes of functional morphology and size of endocrine and mast cell population as well as apudocytes producing serotonin, melatonin, vasointestinal peptides were stated. Apudocyte and mass cell functional morphology, clinical symptoms and mucosal structural changes correlated. Specificity of some parameters in Chron's disease is shown. CONCLUSION: The results may provide additional criteria in diagnosis of different variants of chronic colitis.


Assuntos
Células APUD/ultraestrutura , Doença de Crohn/patologia , Mucosa Intestinal/ultraestrutura , Mastócitos/ultraestrutura , Doenças do Colo Sigmoide/patologia , Células APUD/metabolismo , Adolescente , Adulto , Biópsia , Colite/metabolismo , Colite/patologia , Doença de Crohn/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Mastócitos/metabolismo , Melatonina/metabolismo , Pessoa de Meia-Idade , Prognóstico , Serotonina/metabolismo , Doenças do Colo Sigmoide/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo
8.
Prog Histochem Cytochem ; 34(1): 3-82, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10546282

RESUMO

This review deals with gut endocrine cells in birds. It focuses on both morphological and developmental aspects of these cells, which were included members of Pearse's APUD series. They comprise many cell types, which, in birds as in mammals, produce serotonin and a range of regulatory peptides. The chemical structure of most avian gut peptides has been established. These peptides and their functions are outlined here. The types and distribution of avian gut endocrine cells are detailed and compared with the situation in mammals. In birds, ultrastructural work has been limited to certain types of gut endocrine cell and not as widely applied as in mammals. However, immunocytochemistry has found widespread application in studies on birds: the hatching chick and also the adult chicken and certain other species such as the quail and duck have been studied. Gut endocrine cells showing immunoreactivity for the following peptides/serotonin have been identified: somatostatin, pancreatic polypeptide (PP), peptide YY, glucagon, secretin, vasoactive intestinal peptide, gastrin, cholecystokinin (CCK), neurotensin, motilin, gastrin-releasing peptide, substance P, enkephalin and serotonin. The colocalization of different peptides (including chromogranins) and of peptides and serotonin in the same gut endocrine cells is reviewed: notable amongst such associations are glucagon with PP and gastrin/CCK with neurotensin in the same cells. On morphological grounds cells have been identified as endocrine in avian gut from at least 9 days of incubation. Immunocytochemical studies show the majority of the various types first to appear between 12 to 14 days of incubation, with substantial numbers being recorded from 17 days onwards. Experimental studies on chicken and quail embryos have determined the embryonic origin of gut endocrine cells: evidence is unequivocal that such cells arise from the endoderm, not the neural crest, other ectoderm or the mesoderm. Studies on avian embryos have also contributed to our knowledge of mechanisms controlling the differentiation of gut endocrine cells: evidence shows that gut mesenchyme plays an important role in provoking (or inhibiting) the development of gut endocrine cells and there are indications that the endocrine cell pattern in gut is established early and that an axially-derived factor may be important in this process. The kinds of genetic mechanism possibly involved are mentioned but full elucidation of the processes concerned is awaited. A better understanding of the formation of endocrine tumours of the gut should result from the findings.


Assuntos
Células APUD/citologia , Células APUD/metabolismo , Aves/metabolismo , Hormônios Gastrointestinais/metabolismo , Peptídeos/metabolismo , Sequência de Aminoácidos , Animais , Aves/anatomia & histologia , Aves/embriologia , Diferenciação Celular , Hormônios Gastrointestinais/genética , Histocitoquímica , Dados de Sequência Molecular , Peptídeos/genética
9.
Histochem J ; 29(1): 45-51, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9088944

RESUMO

In earlier studies were determined the effect, presence and ultrastructure of vasoactive intestinal polypeptide (VIP) and 5-hydroxytryptamine (5-HT)-containing nerve fibres in the tilapia and goldfish intestinal mucosa. 5-HT-labelled varicosities were found close to the epithelial cells; however, synaptic membrane specializations have never been observed. VIP-like immunoreactive nerve fibres appear to be located less frequently close to the goldfish epithelium, as in the tilapia intestine, in which the distance between the VIP- or 5-HT-labelled varicosities and the epithelial cells was also rather large (more than 2 micros). To establish a possible role of VIP and 5-HT as neurotransmitters involved in the regulation of fish intestinal epithelium both electron microscopical and immunoelectron microscopical methods were used to visualize the release of 5-HT and VIP from nerve fibres. We found exocytoses from VIP-ergic and serotonergic varicosities in the muscle layers of both fish. Directly underneath the intestinal epithelium of the goldfish, it was demonstrated that 5-HT could be released from scarce varicosities. The release of 5-HT in the tilapia intestinal mucosa could only be observed from endocrine cells.


Assuntos
Sistema Nervoso Entérico/ultraestrutura , Exocitose , Carpa Dourada , Mucosa Intestinal/ultraestrutura , Serotonina/metabolismo , Tilápia , Peptídeo Intestinal Vasoativo/metabolismo , Células APUD/metabolismo , Células APUD/ultraestrutura , Animais , Sistema Nervoso Entérico/metabolismo , Mucosa Intestinal/inervação , Mucosa Intestinal/metabolismo , Microscopia Imunoeletrônica
10.
Arkh Patol ; 58(2): 21-8, 1996.
Artigo em Russo | MEDLINE | ID: mdl-8712935

RESUMO

The paper reviews methods for studying functional morphology of endocrine cells histochemistry and immunohistochemistry, radioautography and methods of ultrastructural verification of secretory granules. Methodological approach is illustrated by the authors' results on the influence of ionizing radiation and tumor growth on the cells of the diffuse endocrine system.


Assuntos
Células APUD/ultraestrutura , Células APUD/metabolismo , Células APUD/efeitos da radiação , Animais , Autorradiografia , Grânulos Citoplasmáticos/ultraestrutura , Histocitoquímica , Imuno-Histoquímica
11.
Zhonghua Bing Li Xue Za Zhi ; 24(5): 303-5, 1995 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-8745479

RESUMO

Fresh gastric carcinoma specimens from 17 cases were collected. The neuroendocrine (NE) cells in gastric carcinoma (GC) and gastric mucosa adjacent to the carcinoma (GMAC) were observed using in situ hybridization of chromogranin A (CgA) oligonucleotide probe and compared with immunohistochemistry of CgA antibody. 5 of the 17 cases of GC showed CgA mRNA positive expression and 7 of the 17 cases expressed CgA protein positively. The simultaneous expression of mRNA and protein of CgA was present in 4 cases. The NE cells in GC not only can store and secrete CgA protein products but also possess the ability to synthesize NE products from gene expression.


Assuntos
Adenocarcinoma/metabolismo , Cromograninas/genética , RNA Mensageiro/análise , Neoplasias Gástricas/metabolismo , Células APUD/metabolismo , Sequência de Bases , Cromogranina A , Mucosa Gástrica/metabolismo , Expressão Gênica , Humanos , Hibridização In Situ , Dados de Sequência Molecular , Sondas de Oligonucleotídeos
12.
Tissue Cell ; 26(3): 309-21, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7915436

RESUMO

The endocrine cells of the rainbow trout (Oncorhynchus mykiss) stomach have been investigated using the immunocytochemical techniques of peroxidase-anti-peroxidase and avidin-biotin-peroxidase complexes on paraffin sections. 33 antisera were tested and eight immunoreactivities were detected: somatostatin-, glucagon- bombesin-, substance P-, serotonin-, met-enkephalin-, CCK/gastrin-, and chromogranin-like containing cells. All of them were present throughout the gastric mucosa except CCK/gastrin-like containing cells that were restricted to the pyloric epithelium. Somatostatin 25 and chromogranin immunoreactive cells are described for the first time in fish stomach. Serotonin immunoreactive cells were also positive for the Grimelius technique and some of them were immunoreactive to anti substance P or anti CCK/gastrin. Immunoreactivities for gastrin 17, gastrin 34 and CCK appeared in the same cells and the absorption controls showed that a molecule containing the carboxi-terminal pentapeptide of this family was present in trout stomach.


Assuntos
Células APUD/metabolismo , Mucosa Gástrica/química , Oncorhynchus mykiss/metabolismo , Peptídeos/análise , Animais , Colecistocinina/análise , Cromograninas/análise , Encefalina Metionina/análise , Mucosa Gástrica/citologia , Gastrinas/análise , Técnicas Imunoenzimáticas , Serotonina/análise
13.
Eur J Histochem ; 38(3): 237-44, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7530517

RESUMO

The presence of endocrine cells was investigated by immunocytochemical procedures in the gut and salivary gland of Viviparus ater, a freshwater prosobranch gastropod. The endocrine cells were scanty and both of closed and open cell type. Most of them were located in the esophagus (immunostaining with anti-gastrin, anti-insulin, anti-serotonin and anti-substance P antisera), very few in the stomach (immunoreactive only to anti-gastrin antibody) and in proximal part of the intestine (immunoreactive to anti-serotonin and anti-substance P antibodies). In the salivary glands, occasional endocrine cells scattered among the glandular cells in the adenomera stained with anti-neuropeptide Y, anti-pancreatic polypeptide and anti-somatostatin sera were detected.


Assuntos
Células APUD/metabolismo , Técnicas Imunoenzimáticas , Intestinos/citologia , Moluscos/anatomia & histologia , Glândulas Salivares/citologia , Células APUD/química , Animais , Hormônios Gastrointestinais/análise , Mucosa Intestinal/metabolismo , Neuropeptídeos/análise , Glândulas Salivares/metabolismo
14.
Cancer ; 70(1 Suppl): 254-68, 1992 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-1350941

RESUMO

Endocrine-paracrine cells of the prostate (also known as APUD or neuroendocrine cells) constitute, in addition to the basal and exocrine secretory cells, a third population of highly specialized epithelial cells in the prostate gland. These endocrine-paracrine cells contain, and most likely secrete, serotonin and calcitonin, as well as variety of other peptides. Little is known of the functional role of these cells, but they probably subserve a paracrine or local regulatory role. They may also regulate via endocrine, lumencrine, or neurocrine mechanisms. These endocrine-paracrine cells probably play a significant role during prostatic growth and differentiation as well as regulating the secretory process of the mature gland. Neuroendocrine differentiation in prostatic carcinoma occurs in the form of the relatively rare small cell carcinoma and carcinoid or carcinoid-like tumor, but most commonly as focal neuroendocrine differentiation in a conventional prostatic adenocarcinoma that is a very frequent, if not ubiquitous phenomenon, and reflects tumor cell heterogeneity mimicking the normal differentiation process. The world's literature on neuroendocrine differentiation in prostatic carcinoma is reviewed. Neuroendocrine differentiation in all types of prostatic carcinoma appears to correlate with a poor prognosis. This correlation is probably multifactorial and may relate to a positive correlation with grade, a direct resistance to hormonal manipulation, and/or autocrine/paracrine growth factor activity due to the secretion of neuroendocrine products. Neuron-specific enolase and chromogranin, as well as other neuroendocrine products, may be useful as serum markers in patients with prostatic carcinoma with neuroendocrine differentiation. New therapeutic strategies need to be developed to treat these tumors. This includes the use of specialized protocols that have been effective against neuroendocrine carcinomas arising in other organ systems.


Assuntos
Células APUD/patologia , Carcinoma/patologia , Próstata/patologia , Neoplasias da Próstata/patologia , Células APUD/citologia , Células APUD/metabolismo , Calcitonina/metabolismo , Carcinoma/diagnóstico , Carcinoma/terapia , Diferenciação Celular , Cromograninas/metabolismo , Humanos , Masculino , Prognóstico , Próstata/citologia , Próstata/metabolismo , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Serotonina/metabolismo
17.
Sov Med ; (12): 7-10, 1990.
Artigo em Russo | MEDLINE | ID: mdl-1982976

RESUMO

Morphologic examination of the adenohypophysis of 46 subjects who died from cardiovascular diseases has shown a restructuring of the gland, including changes in its nonspecific signs and alterations typical of certain cardiovascular conditions. Analysis of the ratios between various types of endocrine cells and different types of basophil tropocytess in health and disease has revealed variability of these parameters in cardiovascular diseases and in various types of the same disease. Fluctuations in adenohypophysis cellular composition are explained by specific features of the pathogenesis of these conditions.


Assuntos
Endocardite Bacteriana/patologia , Adeno-Hipófise/patologia , Cardiopatia Reumática/patologia , Células APUD/metabolismo , Células APUD/patologia , Contagem de Células , Eosinófilos/patologia , Humanos , Mastócitos/patologia , Hormônios Adeno-Hipofisários/metabolismo
19.
Am Rev Respir Dis ; 140(6): 1807-12, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2574971

RESUMO

Pulmonary neuroendocrine cells (PNEC) are granulated epithelial cells distributed throughout conducting airways. Among the bioactive products identified within the secretory granules of these cells are potent mitogens and bronchoactive and vasoactive agents. The secretory status of these cells, which are in greatest number in the fetus and newborn, is modulated by neural reflexes and by changes in airway gas composition. The aggregate data suggest roles for PNEC in airway "chemoception" and/or regulation of airway epithelial differentiation. Marked increases in PNEC are observed in bronchopulmonary dysplasia, where airway and alveolar fibrosis, epithelial metaplasia, and airway and vascular smooth muscle hypertrophy contribute to marked pathophysiologic changes in lung function. Considering the biologic effects of PNEC secretory products, particularly gastrin-releasing peptide on airway epithelial cell and fibroblast proliferation, we propose that an increase in PNEC secretory products in the regenerating airway epithelium may contribute to the development of the pathologic alterations in lung structure seen in bronchopulmonary dysplasia. In this proposed scheme, secretion of abnormally large amounts of bronchoactive and vasoactive agents from PNEC (e.g., serotonin, gastrin-releasing peptide) in response to airway hypoxia and hypercapnia may be partially responsible in the genesis of reactive airway disease and pulmonary hypertension seen in this disease.


Assuntos
Células APUD/fisiologia , Pneumopatias/fisiopatologia , Células APUD/metabolismo , Displasia Broncopulmonar/fisiopatologia , Doença Crônica , Humanos , Recém-Nascido , Pneumopatias/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA