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)

Seventeen human subjects fasted without electrolyte replacement for 3 days and hormone levels were measured before, during and after the fast. Immediate consequences of the fasting state in healthy human subjects include a marked increase in plasma cortisol. ACTH, beta-endorphin, beta-lipotrophic hormone, adrenaline, noradrenaline and dopamine. Levels of all these hormones were much greater on the first morning of the fast than in the post-prandial state, even though the plasma glucose level was no lower than that observed on the morning before the fast began. A clear fall in TSH and tri-iodothyronine (T3) levels was observed, but thyroxine levels did not change significantly. Insulin levels fell whereas proinsulin levels did not fall during the fast, though they did rise markedly upon re-feeding. An increase in GH levels was particularly apparent in male subjects, but was also seen in females when evening samples were compared. Pancreatic glucagon showed a modest rise during the fast, but fell again on refeeding; total glucagon also rose as the fast proceeded, but increased markedly upon re-feeding. Levels of gastrin and peptide YY remained low during the fast. Plasma electrolyte levels were unchanged. The following were closely correlated: cortisol with ACTH, T3 with log10 TSH, dopamine with noradrenaline, and (negatively, during the fast) pancreatic glucagon with glucose.
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PMID:The effect of a 72-h fast on plasma levels of pituitary, adrenal, thyroid, pancreatic and gastrointestinal hormones in healthy men and women. 292 6

SMS 201-995 is an octapeptide analogue of somatostatin. The effect of a single subcutaneous (s.c.) injection of 50 micrograms SMS 201-995 on post-prandial intermediary metabolism was investigated in normal subjects. In spite of a long-lasting post-prandial suppression of insulin secretion, there were no significant changes in the plasma concentration of alanine, glycerol, 3-OH-butyrate or lactate. However, SMS 201-995 impairs carbohydrate tolerance, probably due to inhibition of insulin secretion. Basal and post-prandial plasma concentrations of the gut regulatory peptides pancreatic glucagon, motilin, pancreatic polypeptide, gastric inhibitory polypeptide, enteroglucagon, gastrin and peptide YY were suppressed up to 5 hours after subcutaneous administration of a single dose of SMS 201-995.
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PMID:The effect of a long-acting somatostatin analogue (SMS 201-995) on intermediary metabolism and gut hormones after a test meal in normal subjects. 297 76

Functional and specific receptors for vasoactive intestinal peptide (VIP) (determined by their capacity to bind 125I-VIP and activate adenylate cyclase) and cyclic AMP-dependent phosphodiesterase activities were characterized in enterocytes of human fetal small intestine between 18 and 23 weeks of gestation. Half-maximal stimulation of the cyclase and inhibition of 125I-VIP binding in membrane preparations were respectively observed at 1.4 and 5 X 10(-10) M VIP. The peptides structurally related to VIP activated the cyclic AMP generating system at pharmacological doses (10(-7) M and above) in the following order of potency: VIP greater than PHI greater than GRF greater than secretin. Other peptides or test substances, including GIP, pancreatic glucagon, somatostatin-14, gastrin, CCK, neurotensin, pancreatic polypeptide, PYY, substance P, histamine and isoproterenol are inactive in this system, while the ubiquitous adenylate cyclase activators NaF, forskolin and prostaglandins were effective. These results, combined with the appearance of intestinal VIP in nerve fibers at 8 weeks and with the morphological and enzymatic maturation at 9-12 weeks of the intestinal mucosa, indicate that this neuropeptide may regulate either the differentiation or function of enterocytes during the early development of human intestinal mucosa.
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PMID:Vasoactive intestinal peptide receptor activity in human fetal enterocytes. 298 18

Recent data on the immunolocalization of regulatory peptides and related propeptide sequences in endocrine cells and tumors of the gastrointestinal tract, pancreas, lung, thyroid, pituitary (ACTH and opioids), adrenals and paraganglia have been revised and discussed. Gastrin, xenopsin, cholecystokinin (CCK), somatostatin, motilin, secretin, GIP (gastric inhibitory polypeptide), neurotensin, glicentin/glucagon-37 and PYY (peptide tyrosine tyrosine) are the main products of gastrointestinal endocrine cells; glucagon, CRF (corticotropin releasing factor), somatostatin, PP (pancreatic polypeptide) and GRF (growth hormone releasing factor), in addition to insulin, are produced in pancreatic islet cells; bombesin-related peptides are the main markers of pulmonary endocrine cells; calcitonin and CGRP (calcitonin gene-related peptide) occur in thyroid and extrathyroid C cells; ACTH and endorphins in anterior and intermediate lobe pituitary cells, alpha-MSH and CLIP (corticotropin-like intermediate lobe peptide) in intermediate lobe cells; met- and leu-enkephalins and related peptides in adrenal medullary and paraganglionic cells as well as in some gut (enterochromaffin) cells; NPY (neuropeptide Y) in adrenaline-type adrenal medullary cells, etc.. Both tissue-appropriate and tissue-inappropriate regulatory peptides are produced by endocrine tumours, with inappropriate peptides mostly produced by malignant tumours.
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PMID:Endocrine cells producing regulatory peptides. 329 70

In the present study we report methods for the isolation and culture of colonic peptide YY (PYY) cells and have tested the effects of sodium oleate and other chemotransmitters on PYY release. Enzyme-dispersed canine colonic mucosa cells were separated by a Beckman elutriation rotor, and the enriched PYY fraction was cultured on type I collagen in full growth medium. After 42-48 h of culture PYY cells had selectively adhered to the collagen. Forty to 45% of the adherent cells contained PYY (5.5 +/- 0.5 pmol/24-mm well), and 10-15% of the cells contained glucagon-like immunoactivity (GL29-LI; 0.95 pmol/24-mm well). The effect of various secretagogues on PYY release from these cultures was monitored. Sodium oleate stimulated PYY release in a time-dependent fashion over a dose range from 10 microM to 10 mM. However, sodium oleate at a dose of 100 mM produced disproportionately large PYY release. During a 2-h incubation 5.1% of the total cell content of PYY was released in response to 0.1 mM sodium oleate compared with basal release of 1.1%. At doses less than 10 mM sodium oleate did not release GL29-LI, whereas concentrations of 10 and 100 mM resulted in marked GL29-LI release. These findings suggest that lower concentrations of sodium oleate selectively release PYY, whereas higher concentrations nonselectively induce peptide release probably by effects on membrane stability. We also found that bombesin, epinephrine, and forskolin, but not carbachol, produced time- and dose-dependent release of PYY from these cultures.
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PMID:Primary culture of PYY cells from canine colon. 337 82

We have identified specific binding sites for pancreatic polypeptide (PP) on the mucosal lining of canine small intestine. The present study was undertaken to further characterize these binding sites (receptors) on purified intestinal membranes and to establish their location on the brush border or basolateral surface of the intestinal enterocyte. Basolateral and brush border membranes were prepared by sorbitol density centrifugation. PP receptors were localized predominantly to the vascular surface, and thus binding of PP 125I-labeled on Tyr-27 to the basolateral preparation was used to evaluate receptor characteristics. Binding of PP was calcium, time, temperature, and pH dependent. Maximum specific binding of labeled PP occurred after an 8-hr incubation at 4 degrees C with 5 mM calcium at pH 6.8. Data analysis by Scatchard plot showed high- and low-affinity binding sites with relative affinities of 1.5 x 10(-9) M and 2.6 x 10(-8) M and with corresponding binding capacities of 0.23 pmol/mg and 0.84 pmol/mg of protein, respectively. This receptor was specific for PP since peptide YY and neuropeptide Y, peptides of the PP family, cross-reacted by less than 3%, as judged from comparisons of half-maximal displacement of label. Structurally dissimilar peptides, insulin and glucagon, did not compete for binding. Specific 125I-labeled PP binding was localized primarily to basolateral membranes (9.8 +/- 0.8%) with little binding by brush border membranes (0.8 +/- 0.2%). Thus, we have identified highly specific receptors for PP, located predominantly on the vascular surface of the small intestinal mucosa. These data suggest that the mucosal lining of the small intestine is a target tissue for PP and that PP participates in the hormonal regulation of fuel metabolism and substrate transport in the small intestinal mucosa.
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PMID:Characterization of specific pancreatic polypeptide receptors on basolateral membranes of the canine small intestine. 338 34

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

Electron microscopic immunocytochemistry using protein A-gold labelling of ultrathin sections revealed immunoreactive glicentin (gut-type glucagon) and peptide YY (PYY) in virtually all secretory granules in a population of L-type endocrine cells in feline colon and human rectum. The granules of the human glicentin/PYY cells were considerably smaller in size than those in the cat. In both species the results indicate co-existence of glicentin and PYY in the same secretory granules, despite the probable derivation of the two peptides from two different precursors.
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PMID:Co-existence of glicentin and peptide YY in colorectal L-cells in cat and man. An electron microscopic study. 375 46

Colorectal adenocarcinomas were induced in male Wistar rats, by weekly subcutaneous administration of 1,2-dimethylhydrazine, classified according to the degree of differentiation and submitted to immunocytochemistry for the peptides cholecystokinin (CCK), gastrin, gastric inhibitory polypeptide (GIP), glucagon, neurotensin, pancreatic polypeptide (PP), peptide YY (PYY), somatostatin and vasoactive intestinal polypeptide (VIP) and the biogenic monoamine 5-hydroxytryptamine. Well- or moderately well-differentiated adenocarcinomas comprised 46% of the tumour population, only 4% were poorly-differentiated adenocarcinomas, and the remaining 50% possessed a mixture of these two morphologies. Glucagon, PYY and 5-hydroxytryptamine immunoreactive cells were frequently observed within well- or moderately well-differentiated tumours and within such regions of tumours possessing a mixed morphological pattern. The tumours contained no cells immunoreactive for any of the peptides not normally located within the colorectum, nor did they contain cells immunoreactive for somatostatin and VIP, although known positive controls did stain. Poorly-differentiated tumours and portions of tumours of mixed type, were consistently negative. 5-hydroxytryptamine was the most frequently located of the three antigens, being detected in 87% of the moderately well-differentiated tumours and 32% of the tumours with mixed morphologies. 11% of moderately well-differentiated tumours possessed 5-hydroxytryptamine positive cells in such profusion that they contributed significantly to the tumour mass. The distribution of glucagon- and PYY-immunoreactive cells was similar, although they occurred with a lower frequency, presumably corresponding to their lower numbers within the normal colorectal mucosa. Additionally, these two peptide immunoreactivities were colocalized in the majority of cells, although some cells contained only one antigen.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Neuroendocrine cells within colorectal tumours induced by dimethylhydrazine. An immunocytochemical study. 377

Endocrine cells in 24 primary carcinomas and in the nonneoplastic mucosa of the small intestine were investigated histochemically and immunohistochemically with antisera against serotonin and 10 kinds of peptide hormones. Argyrophil-positive endocrine cells were found in four of eight duodenal, all of eight jejunal, and six of eight ileal carcinomas. The density of the positive cells was higher in the ileal tumors than in the duodenal and jejunal ones. Immunoreactive endocrine cells were detected in three duodenal, six jejunal, and five ileal carcinomas. Immunoreactive serotonin cells were present most frequently and most densely without respect to the site of origin of the carcinomas. In general, the population of endocrine cells among the tumor cells was higher in the ileal carcinomas than in the duodenal and jejunal ones. The ileal carcinomas frequently and densely demonstrated somatostatin, peptide YY, neurotensin, glucagon, and glicentin cells in addition to serotonin cells. The kinds of endocrine cells and the relative frequency of each kind of endocrine cell in carcinomas of the small intestine were similar to those in the nonneoplastic mucosa from which the carcinomas originated. This is the first systematic immunohistochemical study on endocrine cells in carcinoma of the small intestine.
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PMID:Neoplastic endocrine cells in carcinomas of the small intestine: histochemical and immunohistochemical studies of 24 tumors. 380 22


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