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Query: UNIPROT:P01275 (
glucagon
)
26,492
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The biotinyl-tyramide substrate of the horseradish
peroxidase
enzyme has been recently introduced to amplify immunohistochemical signals. We applied either fluorochromeor biotin-conjugated tyramine to improve the detection of different antigens in sections of rat stomach, pancreas, and hypothalamus. A ten- to 100-fold increase in staining efficiency was achieved, depending on the antibody, with either fluorescent or
peroxidase
detection systems. The amplification method was particularly useful for increasing a weak signal of conventional immunostaining caused by suboptimal tissue fixation. At a very low concentration of the primary antibody, the antigen can no longer be detected by a conventional fluorescent secondary antibody but is still detectable after amplification. When an antibody is used at this very low concentration and is detected by a fluorescent amplification method, another primary antibody, raised in the same host species, can be used and demonstrated with a different fluorochrome in subsequent conventional immunostaining of the same section. In this way it becomes possible to immunostain the same section with two different primary antibodies raised in the same host species. Samples for such double immunostaining are demonstrated here using pairs of monoclonal antibodies (to tyrosine hydroxylase and oxytocin) in the hypothalamus and polyclonal antibodies (to
glucagon
and neurofilament M) in sections of rat pancreas. Because in many cases the availability of antibodies is limited, the amplification method can be a quick and efficient tool for double immunostaining with antibodies from the same host species.
...
PMID:Immunohistochemical signal amplification by catalyzed reporter deposition and its application in double immunostaining. 898 27
Our laboratory recently described a new human cytochrome P450 arachidonic acid epoxygenase (CYP2J2) and the corresponding rat homolog (CYP2J3). Immunoblotting studies using a polyclonal antibody raised against recombinant human CYP2J2 confirmed CYP2J protein expression in human and rat pancreatic tissues. Immunohistochemical staining of formalin-fixed paraffin-embedded rat and human pancreas using the anti-CYP2J2 IgG and avidin-biotin-
peroxidase
detection revealed that CYP2J2 protein expression was highly localized to cells in the islets of Langerhans, with minimal staining in pancreatic exocrine cells. Colocalization studies using antibodies to the
glucagon
, insulin, somatostatin, and pancreatic polypeptide as markers for alpha-, beta-, delta-, and PP cells, respectively, showed that CYP2J protein expression was abundantly present in all four cell types, but was highest in the
glucagon
-producing alpha-cells. Direct evidence for the epoxidation of arachidonic acid by pancreatic cytochrome P450 was provided by documenting, for the first time, the presence of epoxyeicosatrienoic acids in vivo in human and rat pancreas by gas chromatography/mass spectrometry. Importantly, the levels of immunoreactive CYP2J2 in different human pancreatic tissues were highly correlated with endogenous epoxyeicosatrienoic acid concentrations. We conclude that human and rat pancreas contain an arachidonic acid epoxygenase belonging to the CYP2J subfamily that is highly localized to islet cells. These data together with previous work showing effects of epoxyeicosatrienoic acids in stimulating insulin and
glucagon
secretion from isolated rat pancreatic islets support the hypothesis that epoxygenase products may be involved in stimulus-secretion coupling in the pancreas.
...
PMID:Predominant expression of an arachidonate epoxygenase in islets of Langerhans cells in human and rat pancreas. 904 44
Histological studies were performed on 24 pancreases of normal human embryos and fetuses aged 7 to 38 weeks. For immunocytochemistry, the avidin-biotin-
peroxidase
method was used to identify and localize insulin,
glucagon
, somatostatin, and pancreatic polypeptide (PP) cells. In 7 wk old embryos, cells containing somatostatin and PP are observed. One week later appear single
glucagon
-positive cells. In the 9th wk, insulin producing cells are visible. During the fetal period two populations of the investigated cells are found: Langerhans islets and dispersed cells. The latter cells containing insulin,
glucagon
or somatostatin are localized in the walls of pancreatic ducts throughout the whole gland, while PP-positive cells are seen mainly in the part of the pancreas, which develops from the ventral anlage (anteroinferior part of the head and adjacent part of the main pancreatic duct). During the development of islets we have observed four stages: (1) scattered cells (7 to 10 weeks); (2) grouping cells (11 to 15 weeks); (3) mantle and zonular islets (10 to 29 weeks), in which B cells located inside are surrounded by a thick zone of A, PP and somatostatin-producing cells; (4) mixed islets (from 30 weeks on) - all cells are scattered over the whole transverse section of the islet. In the developing pancreas, the
glucagon
- and somatostatin-containing cells are the most numerous, while the insulin and PP-containing cells occur in lesser quantities.
...
PMID:Prenatal development of the human pancreatic islets. Immunocytochemical identification of insulin-, glucagon-, somatostatin- and pancreatic polypeptide-containing cells. 927 43
The indirect
peroxidase
method was employed to study the endocrine pancreas of the Cape fur seal. Immunoreactivity to insulin was confined to the cores of the islets and the insulin cells were more abundant than the other endocrine cell types, which occurred mainly in the mantles of the islets. Of these,
glucagon
cells were the most numerous, followed by somatostatin and pancreatic polypeptide (PP) cells. The latter were observed in the mantles of the islets and scattered in the exocrine tissue of the duodenal lobe. The marked variation in the shape and the distribution of the endocrine cells in the mantles of the islets seen in the pancreas of the seal, seems to be typical of carnivorous species like the cat and dog.
...
PMID:The endocrine pancreas of the Cape fur seal, Arctocephalus pusillus (Schreber, 1776): an immunocytochemical study. 946 81
The aim of the present study was to distinguish and describe the patterns of distribution of pancreatic islets within the pancreas of four species of laboratory animals, including rats, dogs, minipigs and monkeys, and furthermore, to identify immunohistochemically various islet cell types and characterize their content. Histopathological examinations were performed on sections stained with hematoxylin and eosin (H&E) and immunostained using rabbit polyclonal antibodies (pAb) against insulin,
glucagon
, pancreatic polypeptide (PP), somatostatin, chromogranin A, keratin, bombesin and gastrin, or mouse monoclonal antibodies (mAb) against synaptophysin, Leu-7 and proliferating cell nuclear antigen (PCNA) in three-step rabbit immunoperoxidase (PAP) and streptavidin/
peroxidase
(StreptABC/HRP) reactions. Positive immunohistochemical reactions were observed in the pancreatic islets of all animal species with all antibodies, except with anti-bombesin and anti-gastrin antibodies. Our results revealed that: 1) there is species specific regional arrangement of islets in the pancreas, 2) each species presents a characteristic distribution of cells producing different hormones. 3) immunoreactivity with immunohistochemical markers varies between species and/or age. The present comparative immunohistochemical study could be helpful for answering questions which are important for understanding some of the intricate mechanisms that govern the integrated function of the endocrine pancreas.
...
PMID:A comparative immunohistochemical study of pancreatic islets in laboratory animals (rats, dogs, minipigs, nonhuman primates). 968 46
Pituitary adenylate cyclase activating polypeptide (PACAP), a member of the secretin/
glucagon
/vasoactive intestinal polypeptide family of peptides, exists as 38-residue (PACAP 38) and truncated 27-residue (PACAP 27) forms, which play various roles in mammals. Recently, we isolated and characterized PACAPs with sequences very similar to that of tetrapod PACAP from the brains of two teleosts, the blue-spotted stargazer Gnathagnus elongatus and the stargazer Uranoscopus japonicus, and located PACAP-like immunoreactivities in the preoptic area, neurohypophysis and medulla oblongata of both species. In this study, PACAP-like immunoreactivity in the brain of an elasmobranch, the stingray Dasyatis akajei, was examined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) and Western blotting analysis and its distribution in the hypothalamo-pituitary region was studied immunohistochemically using the
peroxidase
-antiperoxidase method. The anti-PACAP 27 serum reacted with a single band of whole brain extract with a molecular weight of ca 5000. PACAP-like immunoreactive (LI) neuronal cell bodies were found in the nucleus medius hypothalami and PACAP-LI nerve fibers and terminals were seen from the nucleus to the caudal floor of the infundibular region. These results suggest that PACAP-like peptide may be present and function as a regulatory factor in the hypothalamo-pituitary region of the elasmobranch brain.
...
PMID:The localization of pituitary adenylate cyclase-activating polypeptide (PACAP)-like immunoreactivity in the hypothalamo-pituitary region of an elasmobranch, stingray, Dasyatis akajei. 978 77
Histological studies were performed on 30 pancreases obtained from normal human fetuses aged between the 9th and 38th week. For immunocytochemistry, the avidin-biotin-
peroxidase
method was used to identify and colocalise insulin,
glucagon
, somatostatin, pancreatic polypeptide and proliferating cell nuclear antigen. In the 9th week, cells containing all investigated peptides were present. During the fetal period, two populations of endocrine cells have been distinguished, Langerhans islets and freely dispersed cells. The free cells were polyhormonal, containing insulin,
glucagon
, somatostatin and pancreatic polypeptide, and were localised in the walls of pancreatic ducts throughout the whole gland. During the development of the islets we have observed four stages: (1) the scattered polyhormonal cell stage (9th-10th week), (2) the immature polyhormonal islet stage (11th-15th week), (3) the insulin monohormonal core islet stage (16th-29th week), in which zonular and mantle islets are observed, and (4) the polymorphic islet stage (from the 30th week onwards), which is characterised by the presence of monohormonal cells expressing
glucagon
or somatostatin. Bigeminal and polar islets also appeared during this last stage. The islets consisted of an insulin core surrounded by a thick (in the part developing from the dorsal primordium) or thin rim (part of the pancreas concerned with the ventral primordium) of intermingled mono- or dihormonal
glucagon
-positive or somatostatin-positive cells. The most externally located polyhormonal cells exhibited a reaction for
glucagon
, somatostatin and pancreatic polypeptide. Apart from the above-mentioned types of islets, all arrangements observed in earlier stages were present. Proliferating cell nuclear antigen-positive cells (single in the large islets and more numerous in the smaller ones) were predominantly observed in the outermost layer. Taken together our data indicate that, during the human prenatal development of the islet, endocrine cells are able to synthesise several different hormones. Maturation of these cells involved or depended on a change from a polyhormonal to a monohormonal state and is concerned with decreasing proliferative capacity. This supports the concept of a common precursor stem cell for the hormone-producing cells of the fetal human pancreas.
...
PMID:Polyhormonal aspect of the endocrine cells of the human fetal pancreas. 1046 Apr 68
Glucagon
-like peptides (GLPs) are secreted from enteroendocrine cells in the gastrointestinal tract. GLP-1 actions regulate blood glucose, whereas
GLP-2
exerts trophic effects on intestinal mucosal epithelium. Although GLP-1 actions are preserved in diseases such as diabetes,
GLP-2
action has not been extensively studied in the setting of intestinal disease. We have now evaluated the biological effects of a human
GLP-2
analog in the setting of experimental murine nonsteroidal antiinflammatory drug-induced enteritis. Human (h)[Gly(2)]
GLP-2
significantly improved survival whether administered before, concomitant with, or after indomethacin. h[Gly(2)]
GLP-2
-treated mice exhibited reduced histological evidence of disease activity, fewer intestinal ulcerations, and decreased
myeloperoxidase
activity in the small bowel (P < 0.05, h[Gly(2)]
GLP-2
- vs. saline-treated controls). h[Gly(2)]
GLP-2
significantly reduced cytokine induction, bacteremia, and the percentage of positive splenic and hepatic bacterial cultures (P < 0.05). h[Gly(2)]
GLP-2
enhanced epithelial proliferation (P < 0.05 for increased crypt cell proliferation in h[Gly(2)]
GLP-2
- vs. saline-treated mice after indomethacin) and reduced apoptosis in the crypt compartment (P < 0.02). These observations demonstrate that a human
GLP-2
analog exerts multiple complementary actions that serve to preserve the integrity of the mucosal epithelium in experimental gastrointestinal injury in vivo.
...
PMID:Glucagon-like peptide 2 decreases mortality and reduces the severity of indomethacin-induced murine enteritis. 1056 23
The distribution and relative frequency of endocrine cells in the gastrointestinal tract of the babirusa were studied immunohistochemically using the avidin-biotin-
peroxidase
complex method. Thirteen types of gut endocrine cells were detected; they were immunoreactive for chromogranin, serotonin, somatostatin, gastrin, bovine pancreatic polypeptide (BPP),
glucagon
, secretin, cholecystokinin (CCK), methionine-enkephalin-Arg6-Gly7-Leu8 (MENK8), motilin, gastric inhibitory polypeptide (GIP) and peptide tyrosine tyrosine (PYY). Cells that were immunoreactive for chromogranin, serotonin, somatostatin and
glucagon
were found in all portions of the gastrointestinal tract. MENK8-immunoreactive cells were observed in the stomach and small intestine. Gastrin-immunoreactive cells were detected in the pyloric region and duodenum. PYY-immunoreactive cells were found in the small and large intestine. Cells immunoreactive for motilin, CCK, GIP, and secretin were observed in the proximal small intestine and those immunoreactive for neurotensin were found only in the ileum. Although the distribution pattern of endocrine cells in the gastrointestinal tract of babirusa was similar to those reported for pig, restricted distribution of several endocrine cells, gastrin, BPP, MENK8, motilin, CCK, GIP, secretin and neurotensin and wider distribution of
glucagon
and PYY were observed in the babirusa. The unexpected presence of MENK8 in all glandular regions of the stomach and PYY in the small intestine was also noted. The distribution of gut endocrine cells might be related to the regulatory characteristics of the babirusa digestive tract.
...
PMID:Immunohistochemical study on the distribution of endocrine cells in the gastrointestinal tract of the babirusa, Babyrousa babyrussa (Suidae). 1091 80
AIM:To study the cell types, localization, distribution density and morphology of APUD cells in the intestinal mucosa of stomachless teleost fishes.METHOD:By using the
peroxidase
antiperoxidase complex (PAP) immunocytochemical staining technique the identification, localization and morphology of immunoreactive (IR) endocrine cells seattered in the intestinal mucosa of grass carp (Cyenopharyngodon idellus), black carp ( Mylopharyngodon piceus ) and common carp (Cyprinus carpio) were investigated with 20 kinds of antisera prepared against mammalian peptide hormones of APUD cells, and likewise by using avidin-biotin-
peroxidase
complex (ABC) method those of silver carp (Hypophthalmichthys molitrix), bighead (Aristichthys nobilis), silver crucian carp (Carassius gibelio) and bluntnose black bream (Megalobrama amblyocephala ) were also studied with 5 different antisera. The replacement of the first antiserum by phosphate buffered saline (PBS) was employed as a control. IR endocrine cells were counted with a square-mesh ocular micrometer from 10 fields selected randomly in every section of each part of the intestine specimen. The average number of IR endocrine cells per mm(2) was counted to quantify their distribution density.RESULT:Gastrin (GAS), Gastric inhibitory peptide (GIP),
glucagon
(GLU), glucagons like immunorea-ctants (GLI), bovine pancreatic polypeptide (BPP), leucine-enkephalin (ENK) and substance P (SP)-IR endocrine cells were found in the gut of grass carp, black carp and common carp, and somatostatin (SOM) IR endocrine cells were only seen in common carp. GAS, GIP and GLU-IR endocrine cells were found in the intestinal mucosa of silver carp, bighead, silver crucian carp and bluntnose black bream. Most of IR endocrine cells had the higher distribution density in the foregut and midgut, and were longer in shape. They had a long apical cytoplasmic process extended to the gut lumen and a basal process extended to adjacent cells or basement membrane and touched with it. Sometimes, the basal cytoplasmic process formed an enlarged synapse-like structure in the contiguous part with basement membrane. This phenomenon provided new morpho-logical evidence for neuroendocrine and paracrine secretory function of these enteroendocrine cells.CONCLUTION:At least 8 kinds of IR endocrine cells were found in the gut of stomachless teleost species for the first time in China. These IR endocrine cells scattering in the gut mucosa belong to the APUD system. Among them, the hormones secreted by SP-, ENK-, SOM- and GLU-IR endocrine cells belong to the peptides of dual distribution in the brain and gut. This provided new evidence for the concept of brain-gut peptide. According to the cell types, distribution density, morphological characteristics and variety in shape of APUD cells in the gut of stomachless teleost fishes, it is deemed that the digestive tract of fishes is also an endocrine organ of great importance and complexity.
...
PMID:Immunocytochemical identification and localization of APUD cells in the gut of seven stomachless teleost fishes. 1181 32
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