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)

Synthetic rat and ovine CRF were tested in an in vitro isolated pancreatic islet system for their ability to influence insulin and glucagon release. Acute exposure of islets to both rat and ovine CRF resulted in a significant increase in glucagon release but only over a narrow range of concentration (50-200 pg/ml). Neither peptide had a significant effect on insulin release. Our results raise the possibility that release of glucagon may be stimulated by CRF as part of the overall response to stress.
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PMID:Corticotropin-releasing factor: its action on the islets of Langerhans. 389 22

Corticotropin-releasing factor-containing cells have been recently found in the endocrine pancreas of several vertebrate species by immunocytochemistry. In order to clarify the possible physiological significance of these findings, we have studied the effect of the administration of CRF on endocrine pancreatic function. Five minutes, after injection of ovine CRF 1-41 into the jugular vein, a dose-related increase in insulin levels in the hepatic-portal vein of anesthetized rats was found. This dose-dependent insulin increase was delayed to fifteen minutes after CRF injection into rats exposed to greater surgical stress and was partially blunted in adrenalectomized animals. Glucose and glucagon levels were not altered after CRF administration under these conditions. These results suggest that CRF may play a modulatory role in insulin secretion; however, whether CRF acts directly on the beta-cell or through some CRF-stimulated mediator remains to be established.
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PMID:Stimulation of insulin secretion by corticotropin-releasing factor (CRF) in anesthetized rats. 608 46

As a CRF-like peptide has been isolated from human gut, we investigated the effect of synthetic CRF-41 100 micrograms on gut and pancreatic peptides in six normal subjects. There was a significant rise in pancreatic polypeptide compared to a control infusion, but no change in plasma insulin, pancreatic glucagon, gastrin, somatostatin, motilin, neurotensin, gastric inhibitory peptide, or cholecystokinin was seen. In addition, there was no change in circulating met-enkephalin. We conclude that the rise in pancreatic polypeptide seen after CRF administration may suggest a role for a CRF-like peptide in the control of pancreatic function.
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PMID:Corticotrophin releasing factor: effects on circulating gut and pancreatic peptides in man. 614 13

CRF has been detected in the endocrine pancreas by immunocytochemistry with an antiserum that recognizes mainly the C-terminal portion of CRF-41. CRF-containing cells have been shown to be present in the pancreas of representative species of fishes, amphibians, reptiles, birds, and mammals including man. Light and electron microscopic observations indicate that the CRF-containing cells in the endocrine pancreas are similar to glucagon (A) cells both in their morphology and distribution. Individual CRF-containing cells are also found scattered in the exocrine pancreas in all species studied. In addition, CRF-containing cells have been identified in the human, monkey, cat, and rat stomach and small intestine. Recent reports also indicate that CRF-like immunoreactivity is present in the circulating blood, the adrenal medulla, and the placenta. Finally, several peripheral (pancreas, stomach, colon, lung and thyroid) tumors which produced corticotropin-releasing substances have been described by others. Although the peripheral actions of CRF are not yet known, these observations indicate that it is widely distributed in peripheral tissues and it may also represent a new tumor marker.
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PMID:Corticotropin-releasing factor (CRF)-like immunoreactivity in the gastro-entero-pancreatic endocrine system. 638 55

Hypothalamic mechanisms of neurohormone regulation of endocrine pancreas in diabetes mellitus, adaptation to hypoxia and their combination were studied on Wistar rats. To evaluate the condition of supraoptic nucleus (SON) secretory function, paraventricular subnuclei (PVH) of hypothalamus and endocrine pancreas, we used radioimmunoassay, immunocytochemical, morphometrical and histochemical methods. Hyperglycemia, hypoinsulinemia, glucagon and somatostatin synthesis and secretion intensification in diabetes mellitus is accompanied by marked reorganization of hypothalamic neurohormones (CRF, vasopressin, oxytocin) secretion with corresponding signs of activity increase of synthesizing their hypothalamus nuclei and subnuclei and also ACTH, corticosterone, cortisol rise in blood. Adaptation to hypoxia caused hypoglycemia, activated insulin biosynthesis, changed glucagon and somatostatin synthesis and secretion. CRF concentration, corticosterone and cortisol, ACTH in blood was not changed, vasopressin concentration lowered, oxytocin in median eminence of hypothalamus increased to a higher degree than in diabetes. Adaptation to hypoxia corrected impaired hormone balance and state of Langerhans islets (beta-cells destruction process inhibition, insulin biosynthesis stimulation, glucagon and somatostatin secretion decrease) in diabetes mellitus, hypothalamic neurohormones participating in this process.
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PMID:[The vasopressin-, oxytocin- and corticoliberin-synthesizing structures of the hypothalamus in rats with diabetes mellitus under hypoxic exposures]. 790 84

Hyperglycemia, hypoinsulinemia, and an increase of glucagon and somatostatin concentration under diabetes mellitus are accompanied by intensification of secretion of hypothalamic neurohormones (CRF, vasopressin, oxytocin, somatostatin) with the corresponding signs of the increase in activity of hypothalamus nuclei and subnuclei secreting them as well as ACTH, corticosterone and cortisol rise in blood. Adaptation to hypoxia has caused hypoglycemia, activated insulin biosynthesis, changed glucagon and somatostatin synthesis and secretion. CRF corticosterone, cortisol and ACTH concentration in blood was not changed, vasopressin concentration lowered, somatostatin and oxytocin amount (in hypothalamus) increased to a higher degree than under diabetes. Adaptation to hypoxia corrected impaired hormone balance and state of Langerhans islets (beta-cells destruction process inhibition, insulin biosynthesis stimulation, glucagon and somatostatin secretion decrease) under diabetes mellitus, hypothalamus neurohormones participating in this process.
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PMID:[Hypothalamic mechanisms of neurohormone regulation of the endocrine part of the pancreas]. 790 82

During the past 20 years, several bioactive peptides have been identified in teleost fishes that subsequently have been shown to play important regulatory roles in mammalian physiology. The urophysis, corpuscles of Stannius and Brockmann body are anatomical structures particular to fish that have no obvious counterpart in mammals. Extracts and/or cDNA libraries prepared from these tissues have been used to identify for the first time urotensin II (U-II), urotensin-I (U-I), stanniocalcin and glucagon-like peptide-1 (GLP-1). Although U-II and U-I were originally regarded as exclusively the products of the teleost urophysis, the peptides have a wide phylogenetic distribution across the vertebrate lineage, including mammals. U-II is localized to motor neurones in the human spinal cord and is a potent vasoconstrictor that may be implicated in the pathogenesis of heart failure. The human ortholog of urotensin-I is urocortin which is synthesized in selected regions of the brain and is the endogenous ligand for the CRF type 2 receptor. Urocortin is believed to important in mediating the effects of stress on appetite. Stanniocalcin is involved in maintaining calcium and phosphate homeostasis in teleost fish. An ortholog of stanniocalcin has a widespread distribution in mammalian tissues and is postulated to regulate renal phosphate excretion and to protect neurons against damage during cerebral ischemia. The biological actions and therapeutic potential of GLP-1 in humans are now fully appreciated but the peptide was first identified as a domain in a preproglucagon cDNA prepared from anglerfish Brockmann bodies. In contrast to mammalian preproglucagons, GLP-1 is present in anglerfish preproglucagon as the bioactive, truncated sequence [corresponding to human GLP-1(7-37)] rather than the inactive, N-terminally extended form [corresponding to GLP-1(1-37)]. Failure to appreciate the significance of this fact retarded progress in the field for several years.
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PMID:Singular contributions of fish neuroendocrinology to mammalian regulatory peptide research. 1103 47


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