Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of a number of peptides which are found in the gastrointestinal tract have been ascertained on the direct current recorded dorsal and ventral root responses of the isolated hemisected toad spinal cord. Motilin, substance P, bombesin, neurotensin, and thyrotropin releasing hormone had potent depolarizing actions on dorsal root terminals and motoneurons. These substances evoked discernable effects at concentrations as low as 10--7 M, or even lower with motilin. The effects of motilin, neurotensin, and thyrotropin-releasing hormone were greatly reduced or abolished by perfusion of the preparation with tetrodotoxin. Adrenocorticotrophic hormone, secretin, and pancreozymin (cholecystokinin) also depolarized dorsal root terminals and motoneurons. The effects of secretin and cholecystokinin were not abolished by tetrodotoxin. Leu- and Met-enkephalin had weak hyperpolarizing actions on the dorsal and ventral root potentials of repetitively stimulated preparations. Gastrin, gastric inhibitory peptide, glucagon, and somatostatin had no apparent effects on the responses of the preparation. Angiotensin and vasopressin both had rather weak depolarizing effects on the dorsal and ventral roots.
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PMID:Actions of various gastrointestinal peptides on the isolated amphibian spinal cord. 11 60

The endocrine cells of rainbow trout pyloric ceca and intestine have been investigated immunocytochemically using the avidin-biotin method. Twenty-six antisera were tested and 13 endocrine cell types immunoreacted with antisera to serotonin, somatostatin-25, bombesin, C-flanking bombesin, substance P, salmon PP, NPY, PYY, PP, glucagon, GLP1, Met-enkephalin, and CCK/G. Glucagon and GLP1 immunoreactivities appear in the same cells. Nerves positive to serotonin, substance P, PHI, and VIP were also found. The presence of cells positive to somatostatin-25, C-flanking bombesin, and salmon PP are described for the first time in fish intestine.
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PMID:Endocrine cells and nerves in the pyloric ceca and the intestine of Oncorhynchus mykiss (Teleostei): an immunocytochemical study. 138 78

An immunocytochemical investigation was carried out on round and spreading hemocytes of Planorbarius corneus by using 20 antisera to vertebrate bioactive peptides. The immunotests showed the presence of alpha 1-antichymotrypsin-bombesin-, calcitonin-, CCK-8 (INC)-, CCK-39-, gastrin-, glucagon-, Met-enkephalin-, neurotensin-, oxytocin-, somatostatin-, substance P-, VIP-, and vasopressin-immunoreactive molecules in the spreading hemocytes. The round hemocytes were only positive to anti-bombesin, anticalcitonin, anti-CCK-8 (INC), anti-CCK-39, anti-neurotensin, anti-oxytocin, anti-substance P and anti-vasopressin antibodies. No immunostaining was observed with anti-CCK-8 (Peninsula), anti-insulin, anti-prolactin, anti-thyroglobulin and anti-thyroxin (T4) antibodies. As probably in vertebrates, these bioactive peptides may modulate immuno cell function.
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PMID:Immunocytochemical evidence of vertebrate bioactive peptide-like molecules in the immuno cell types of the freshwater snail Planorbarius corneus (L.) (Gastropoda, Pulmonata). 169 11

The gastro-entero-pancreatic (GEP) endocrine system of a stomach-containing and of a stomachless teleost, Sparus auratus and Barbus conchonius, respectively, are studied immunocytochemically using different antisera against mammalian hormones. Insulin-, glucagon-, somatostatin-, and pancreatic polypeptide (PP)-immunoreactive cells are identified in the endocrine pancreas of both species. Only the distribution of PP-immunoreactive cells differed strongly; in the principal islet of both fishes, few PP-immunoreactive cells are present, whereas in the smaller ones many of them are observed in S. auratus and none in B. conchonius. In the digestive tract of S. auratus 10 endocrine cell types can be distinguished: neurotensin-, secretin-, serotonin-, somatostatin-, and two types of substance P-immunoreactive cells exclusively in the stomach, and C-t-gastrin/CCK-, glucagon-, Met-enkephalin-, PP-, and only one type of substance P-immunoreactive cells in the intestinal epithelium. With the exception of substance P-immunoreactive cells, the other four intestinal endocrine cells, as well as an unspecific immunoreactive cell, can also be found in B. conchonius. Coexistence of glucagon- and PP-like immunoreactivity is observed in the pancreas of S. auratus and in the gut of B. conchonius. Pancreatic and gut endocrine cells showing only PP- or glucagon-like immunoreactivity are found, too.
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PMID:A comparative immunocytochemical study of the gastro-entero-pancreatic (GEP) endocrine system in a stomachless and a stomach-containing teleost. 288 63

Specific binding of vasoactive intestinal peptide (VIP) to epithelial cell membranes of rat ventral prostate was reversible, saturable and dependent on time and temperature. The data suggested the presence of two classes of VIP receptors: a class with high affinity (Kd = 1.7 nM) and low binding capacity (0.5 pmol VIP/mg protein), and another class with low affinity (Kd = 36.2 nM) and high binding capacity (7.5 pmol VIP/mg protein). Chicken VIP and porcine secretin recognized VIP receptors but exhibited a 10-fold higher and a 40-fold lower affinity than porcine VIP, respectively. However, glucagon, somatostatin, Met-enkephalin and cholecystokinin were ineffective. GTP inhibited markedly the interaction of VIP with membranes by increasing the rate of dissociation of peptide bound to its receptors. GDP and Gpp(NH)p behaved as GTP but other purine nucleotides and nucleosides did not show any effect.
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PMID:VIP binding to epithelial cell membranes of rat ventral prostate: effect of guanine nucleotides. 299 70

The endocrine cells in the gut of Mugil saliens Risso, 1810 (leaping grey mullet) were investigated by immunocytochemical and electron microscopic techniques. Gastrin-, glucagon-, and somatostatin-immunoreactive cells were identified in the cardiac and cecal stomach regions, located mainly in the lower part of the gastric folds and in the upper part of the glands. Substance P-, somatostatin-, and pancreatic polypeptide (PP)-immunoreactive cells were found between epithelial cells in the pyloric stomach region. Gastrin-, cholecystokinin (CCK)-, gastric inhibitory polypeptide (GIP)-, substance P-, Met-enkephalin- and PP-immunoreactive cells were observed throughout the intestine while only the last three of these appeared in the posterior intestine. Nine types of gastroenteroendocrine cells were ultrastructurally characterized; some of them were related to the cell types immunocytochemically identified.
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PMID:The endocrine cells in the gut of Mugil saliens Risso, 1810 (Teleostei): an immunocytochemical and ultrastructural study. 329 46

Carcinoid tumors of the middle ear are rare, with only three previously reported cases. The authors report the light and electron microscopic and immunohistochemical features of two carcinoid tumors that occurred in a 34-year-old female and a 21-year-old male. Both presented with unilateral hearing loss. By light microscopic examination, both were characterized by trabecula of tall columnar cells with basal nuclei and no mitotic activity. Electron microscopic examination demonstrated large numbers of pleomorphic neurosecretory granules, perinuclear aggregates of intermediate filaments, cell junctions, and surface microvillous processes. Some cells contained intermediate filaments forming tonofilaments and lacked secretory granules. These cells stained for cytokeratin by immunoperoxidase and separated the neuroendocrine cells from the underlying basal lamina. The cells in this tumor stained for the molluscan cardioexcitatory peptide. Cells in both tumors also stained for pancreatic polypeptide. Neither case stained for lysozyme, insulin, glucagon, somatastatin, gastrin, substance P, thyroid-stimulating hormone, adrenocorticotropic hormone, Met-enkephalin, Leu-enkephalin, neuropeptide Y, peptide YY, neurotensin, Bombesin, serotonin, neuron-specific enolose, glial and neural filaments, S-100 protein, cholecystokinin, beta-endorphin, beta-human chorionic gonadotropin, luteinizing hormone/follicle-stimulating hormone, vasoactive intestinal polypeptide, prolactin or calcitonin. Carcinoid tumor of the middle ear can be distinguished from paraganglioma and middle ear adenoma.
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PMID:Carcinoid tumors of the middle ear. 357 33

1. The effects of secretin, glucagon, cholecystokinin-pancreozymin (CCK-PZ), gastric inhibitory peptide (GIP), vasoactive intestinal peptide (VIP), somatostatin, neurotensin and enkephalin on basal, pentagastrin- and histamine-stimulated gastric acid secretion were investigated in the conscious fistula rat. 2. Glucagon and GIP were ineffective inhibitors of basal and pentagastrin-stimulated secretion. CCK-PZ stimulated acid secretion at a low dose level but at higher doses it inhibited both pentagastrin- and histamine-induced secretions. VIP was ineffective at low doses and at high doses its action was complicated by reflux of stimulated pancreatic and intestinal secretions into the stomach. Met-enkephalin inhibited histamine- but not pentagastrin-stimulated secretion. Neurotensin inhibited the response to pentagastrin but had no effect on histamine-stimulated secretion. Secretin and somatostatin were potent inhibitors of basal and pentagastrin-stimulated acid secretion with little or no effect on the response to histamine. 3. At doses completely inhibitory to pentagastrin-stimulated secretion secretin and somatostatin did not block the mobilization of gastric mucosal histamine by pentagastrin, although somatostatin caused partial competitive inhibition at lower doses of pentagastrin. Thus secretin and somatostatin inhibited pentagastrin-induced secretion neither by blocking gastric mucosal histamine mobilization nor by abolishing the direct action of histamine on the parietal cell -- findings which are inconsistent with the proposed role of histamine as the mediator of the action of gastrin on the parietal cell.
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PMID:Effects of various gastrointestinal peptides on parietal cells and endocrine cells in the oxyntic mucosa of rat stomach. 610 65

We have prepared a fluorescent conjugate of porcine calmodulin with 5-(dimethylamino)-1-naphthalene-sulfonyl chloride that is highly sensitive to both calcium binding and protein binding. We have used the fluorescence of this conjugate in addition to the intrinsic peptide fluorescence to show that adrenocorticotropic hormone (ACTH), beta-endorphin, glucagon, and substance P undergo calcium-dependent binding by calmodulin, with competition for common binding sites. The dissociation constants determined in the presence of 0.85 mM CaCl2 and 0.2 N KC1, pH 7.3 at 25 degrees C, range from 1.5 muM to 3.4 muM. The alpha-melanocyte-stimulating hormone, bombesin, and somatostatin also bind, with dissociation constants between 60 muM and 90 muM. Angiotensins I and III, bradykinin, neurotensin, physalaemin, substance P octapeptide, insulin, and Leu- and Met-enkephalin show little or no binding. Sequence comparisons show that the peptides that bind calmodulin well contain regions structurally similar to the recognition sequence for the cAMP-dependent protein kinase and to the sequences surrounding phosphorylated serine residues in several calmodulin binding proteins. This result suggests that modification of calmodulin binding sites in calmodulin-dependent proteins is one of the functions of protein kinase. Calcium has a dual role in peptide binding by calmodulin. The occupation of calcium binding sites having a pK approximately 4 results in a 2-fold increase in peptide binding affinity.
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PMID:Binding of simple peptides, hormones, and neurotransmitters by calmodulin. 618 Jul 61

A biologically active gastrin analogue, [125I](Nle11)-HG-13, appears to bind specifically to saturable binding sites on isolated rabbit gastric mucosal cells: Kd = 70 pM at pH 7.4 and at 37 degrees C. Increasing incubation temperature from +4 degrees C to +37 degrees C increased specific binding. Gastrin binding was shown to be reversible and the dissociation rate was enhanced with cold gastrin. The binding sites were saturated with 0.2 fmol of labelled gastrin per 10(6) mucosal cells. Gastrin binding was not inhibited by secretin, glucagon, Met-enkephalin, physalaemin, eledoisin, BPP, VIP, carbachol, histamine, atropine or cimetidine. Gastrin analogues (HG-4, HG-8, (Leu15)-HG-17), CCK-7 and gastrin antagonists (proglumide or benzotript) inhibited [125I](Nle11)-HG-13 specific binding. We concluded that isolated cells from rabbit gastric fundic mucosa contain high-affinity binding sites for a gastrin analogue (Nle11)-HG-13.
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PMID:High-affinity binding sites for gastrin on isolated rabbit gastric mucosal cells. 629 Feb 32


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