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Search Results: 1 - 10 of 9048 matches for " Endocrine cells "
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Immunocytochemical study of the distribuition of endocrine cells in the pancreas of the Brazilian sparrow species Zonotrichia Capensis Subtorquata (Swaison, 1837)
Nascimento, AA;Sales, A;Cardoso, TRD;Pinheiro, NL;Mendes, RMM;
Brazilian Journal of Biology , 2007, DOI: 10.1590/S1519-69842007000400021
Abstract: 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.
Ghrelin- and preproghrelin-immunoreactive cells in atrophic body gastritis
Moreira, Letícia F;Barbosa, Alfredo J. A;
Jornal Brasileiro de Patologia e Medicina Laboratorial , 2011, DOI: 10.1590/S1676-24442011000500009
Abstract: introduction: ghrelin is a 28 amino acid peptide mainly secreted by endocrine cells of the gastric mucosa, which is believed to have a modulating effect on cell growth. objective: to assess the presence of ghrelin and its precursor preproghrelin molecule in endocrine hyperplasias associated with atrophic body gastritis (abg). material and methods: endoscopic biopsies from 54 patients with abg were processed for immunohistochemistry and specific antibodies against ghrelin, preproghrelin and chromogranin were applied. we assessed the immunoreactive cells in endocrine hyperplasia from the atrophic mucosa and intestinal and pseudo-antral metaplasia areas. results: there was ghrelin expression in a variable number of hyperplastic endocrine cells from all patients studied. there was a statistically significant difference in the number of hyperplastic nodules with more than 50% immunostained cells for chromogranin and ghrelin and for chromogranin and preproghrelin. the mean number of hyperplastic nodules identified by chromogranin was 8.6 per patient. most nodules were immunoreactive to ghrelin and preproghrelin. the presence of ghrelin and preproghrelin expression was uncommon in glands showing intestinal metaplasia: four (9.5%) and nine (21.4%) cases, respectively. in contrast, they were relatively frequent in pseudo-antral metaplasia areas: 37 (72.5%) and 26 (50.9%) cases, respectively. conclusion: ghrelin- and preproghrelin-immunoreactive cells are frequently present in endocrine hyperplasias associated with abg. however, further studies are required to determine to what extent these hormones act as modulators of hyperplastic nodular growth and evolution.
Endocrine cells and nerve ganglia of the small intestine of the Opossum Didelphis aurita Wied-Neuwied, 1826 (Mammalia: Didelphidae)
Freitas-Ribeiro, Gláucia M.;Fonseca, Cláudio C.;Sartori, Sirlene S.R.;Loures-Ribeiro, Alan;Neves, Clóvis A.;
Anais da Academia Brasileira de Ciências , 2012, DOI: 10.1590/S0001-37652012005000045
Abstract: the nervous and endocrine systems jointly control intestinal movements, secretions of their glands and also participate of the processes of nutrient digestion and absorption. therefore, the central objective of this study was to verify the existence of a possible relationship between the number of nervous cells and ganglia of the submucosal and myenteric plexuses and the number of endocrine cells in the small intestine of adult d. aurita. the utilized staining techniques were grimelius, modified masson-fontana, direct immunoperoxidase and h-e. argyrophillic, argentaffin and insulin immunoreactive endocrine cells do not numerically vary between the initial, mid and final regions of the duodenum, jejunum and ileum (p>0.05), except for argyrophillic cells in the jejunum (p>0.05). no numerical relationship has yet been verified between the number of nerve ganglia and endocrine cells, and also between nervous and endocrine cells. we recommended the use of new immunohistochemical techniques to confirm the numerical correlation between the nervous and endocrine systems in the small intestine. the morphology and distribution of endocrine cells and the nerve ganglia studied were similar to those encountered in eutherian mammals.
Ultrastructure of two Types of Endocrine Cells in the Midgut Epithelium of Spodoptera Exiqua H bner, 1808 (Insecta, Lepidoptera, Noctuidae)
Magdalena M. Rost-Roszkowska , Agata Chechelska , Maciej Fr dczak , Katarzyna Salitra
Zoologica Poloniae , 2008, DOI: 10.2478/v10049-008-0003-6
Abstract: Midgut epithelium of Lepidoptera consists of four types of cells: columnar, goblet, endocrine and regenerative. Among endocrine cells two types have been distinguished: "open" and "closed". In all five larval instars of Spodoptera exiqua (Lepidoptera, Noctuidae) only "open" endocrine cells were observed, which means that their apical membranes contact with the midgut lumen and form microvilli like columnar cells of epithelial character. Among them granular and vesicular cells are distinguishable. The number of vesicular endocrine cells increases distinctly in the 5th larval instar. The structure of endocrine cells in the midgut epithelium of S. exiqua and their differentiation from the regenerative cells, studied in transmission electron microscope, are described.
Ghrelin endocrine cells in the human stomach during prenatal and early postnatal development
Mitrovi? Olivera,Mi?i? Mileva,Todorovi? Vera,Radenkovi? G.
Archives of Biological Sciences , 2011, DOI: 10.2298/abs1101021m
Abstract: The aim of this study was to investigate the appearance, localization and density of ghrelin cells in the human stomach during prenatal development. For this purpose the antrum and corpus of embryos, fetuses and infants are stained immunohistochemically by the streptavidin-biotin technique. The presence of P/D1 cells at 11 weeks of fetal development, their highest density during the first detection and higher density in the corpus than in antrum, and their localization in the glandular base of stomach gland, all suggest that ghrelin plays a major role in the early stages of the developing stomach.
Apoptosis-inducing activity of endocrine-disrupting chemicals in cultured PC12 cells  [PDF]
Harue Sasaya, Kazuya Yasuzumi, Hiroki Maruoka, Ayumi Fujita, Yuichi Kato, Taiki Waki, Koji Shimoke, Toshihiko Ikeuchi
Advances in Biological Chemistry (ABC) , 2012, DOI: 10.4236/abc.2012.22012
Abstract: Endocrine-disrupting chemicals (EDCs) are known to exert estrogen-like effects that are similar to those made by naturally produced hormones or by inhibition of the receptors in the cell receiving the hormones. Recently, several reports have indicated that EDCs can affect the developing central nervous system. In our current study, we report that some EDCs induce apoptosis in cultured PC12 cells and can be classified into three groups. Bisphenol A (BPA), p-nonylphenol (NP) and tributyltin chloride (TBT) were found to induce endoplasmic reticulum (ER) stress-associated apoptosis and activate the unfolded protein response (UPR) system, whereas benomyl (beno) induced non-ER stress-associated apoptosis. The half-maximal apoptosis-inducing concentrations (IC50) of these EDCs were 160 μM for BPA, 25.6 μM for NP, 640 nM for TBT and 48 μM for beno. Although these concentrations are higher than those found in the environment, some EDCs may have apoptotic effects on various cells in the body, including neurons, through their accumulation in the body over time or condensation through the food chain. On the other hand, benzopyrene, fenvalerate, styrene monomer and bis(2-ethylhexyl)phthalate did not induce apoptosis in PC12 cells. We analyzed also whether apoptosis-inducing EDCs had an estrogen-like effect on cultured PC12 cells transfected with a luciferase reporter plasmid, the activity of which is dependent on estrogen receptor α. We found that BPA had an estrogen-like effect (EC50 = 5.9 μM) but that NP, TBT and beno did not in transfected PC12 cells. These results suggest that BPA may predomi-nantly exert estrogenic effects, but others may pre-dominantly have apoptosis-inducing effects on cells in the body exposed to a polluted environment.
Immunocytochemical study of gastrintestinal endocrine cells in insectivorous bats (Mammalia: Chiroptera)
Santos, CM.;Nascimento, AA.;Peracchi, AL.;Sales, A.;Mikalauskas, JS.;Gouveia, SF.;
Brazilian Journal of Biology , 2008, DOI: 10.1590/S1519-69842008000300026
Abstract: the regional distribution and relative frequency of endocrine cells in the stomach and intestine of phyllostomidae: lonchorhina aurita and molossidae: molossus molossus bats were studied immunohistochemically. three types of immunoreactive (ir) endocrine cells - to serotonin (5-ht), gastrin (gas) and enteroglucagon (gluc) - were found in the gastric mucosa and four types of ir cells were identified in the intestinal mucosa. this study showed an interespecfic difference in the regional distribution and relative frequency of endocrine cells in the chiropteran alimentary tract.
DYNAMICS OF DIFFERENTIATION OF CHROMOGRANIN A-IMMUNOREACTIVE ENDOCRINE CELLS AND MYENTERIC PLEXUS OF THE HUMAN FETAL DUODENUM IN THE THIRD AND THE FIFTH MONTH OF DEVELOPMENT
Ivan Nikoli?,Vera Todorovi?,Vladimir Petrovi?,Aleksandar Petrovi?
Acta Facultatis Medicae Naissensis , 2010,
Abstract: The aim of the paper was to examine the neuroendocrine differentiation of endocrine cells and neurons of myenteric plexus of fetal duodenum. The material consisted of duodenums of 14 fetuses of different gender, in the third and fifth month of gestational age. Fetal duodenal tissue was fixed in the Bouin solution, routinely processed and embedded in paraffin blocks, from which were made the sections stained with HE and PAP immunostaining method for identification of chromogranin A (Cg A), marker of neuroendocrine differentiation. The number of endocrine cells was quantified by determining the numerical areal density, while the morphological development of myenteric plexus was determined by measuring its area. There is a large number of Cg A-immunoreactive endocrine cells in the mucosis of duodenum in the third and fifth month of development. These cells show a high degree of polymorphism in shape, size and immunoreactivity. No significant difference was observed in the number of cells in the epithelium of duodenum in the third and the fifth month of development. At the same time, myenteric plexus was significantly more developed in the duodenum in the fifth month of fetal development compared to the third month. The results indicate that the differentiation of Cg A-immunoreactive cells occurs earlier in the epithelium of the duodenum than in neurons of myenteric plexus.
Immunohistochemical study of the digestive tract of Oligosarcus hepsetus
Danielle A Vieira-Lopes,Nadja L Pinheiro,Armando Sales,Adriana Ventura
World Journal of Gastroenterology , 2013, DOI: 10.3748/wjg.v19.i12.1919
Abstract: AIM: To describe the histology of the digestive tract and to investigate the occurrence of endocrine cells in Oligosarcus hepsetus (O. hepsetus). METHODS: The digestive tract (DT) of O. hepsetus was divided into esophagus, two stomach regions (glandular and non-glandular) and two intestinal regions (anterior and posterior). These specimens were processed by routine histological techniques and stained with hematoxylin-eosin, Gomori’s trichrome, periodic acid Schiff (PAS) and Alcian blue (AB). An immunohistochemical method using avidin-biotin-peroxidase was employed. RESULTS: The esophagus is lined with a non-keratinized stratified squamous epithelium that is reactive to PAS and AB. The stomach has a mucosa lined with a simple columnar epithelium with mucus-secreting cells that are reactive only to PAS. The intestine has a simple columnar epithelium with a brush border and goblet cells that are reactive to PAS and AB. Somatostatin, serotonin and cholecystokinin immunoreactive cells were identified throughout the DT. CONCLUSION: This study revealed adaptations for the species’ diet and showed that the distribution and relative frequency of immunoreactive cells are similar to those of other fish.
Ultrastructure characteristic of the endocrine cells of prostate in poorly differentiated adenocarcinoma
Prokopyuk O.V.,Volkov K.S.,Kurik O.G.
Морфолог?я , 2008,
Abstract: A research purpose was a ultrastructural study of prostatic APUD-system at poorly differentiated adenocarcinoma. The electron-microscopic investigation of the endocrine cells of prostate in 6 patients with poorly differentiated adenocarcinoma and fragments of 3 prostates without a tumour process (control group) was performed. Both the increase of the morphofunctional activity and presence of dystrophic changes of endocrine cells of prostate was found. At tumours, built from dark cells, APUD-cells are in less, contain less of endocrine granules, what in light-cell adenocarcinoma, where their amount is comparative anymore and in a cytoplasm them there is a far of secretory granules.
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