Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Administration of cysteamine (mercaptoethylamine) induces in rats severe perforating duodenal ulcers. Because the ulcerogenic properties of cysteamine are markedly reduced by treatment with somatostatin, we considered the possibility that cysteamine-induced duodenal ulcer might be mediated by depletion of tissue somatostatin, and thereby of its paracrine influences on gastrin and gastric acid secretion. To test this hypothesis, we measured the concentration of immunoreactive somatostatin (IR-somatostatin) in stomach and duodenal mucosa at intervals after administration of a single ulcerogenic dose (30 mg/kg by stomach tube). IR-somatostatin in these tissues fell rapidly to reach a minimum at 4 h (stomach 31%, duodenum 60% of control respectively). IR-somatostatin in hypothalamus and pancreas decreased gradually to a minimum at 7 h. Another duodenal ulcerogen, propionitrile (10 mg/100 g bw, s.c.) which is more toxic than cysteamine, and several stressful procedures including ether anesthesia, restraint and s.c. formalin did not lower stomach or duodenal IR-somatostatin. Gut, pancreas and hypothalamic VIP levels were not influenced by cysteamine. These findings suggest that cysteamine is a relatively specific depletor of tissue somatostatin. Because blood levels of somatostatin fell, and only trivial amounts of the peptide were found in the stomach lumen after cysteamine administration, it appears likely that this agent acts at the cellular level to cause breakdown of preformed somatostatin and/or to acutely reduce its synthesis.
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PMID:Somatostatin in rat tissues is depleted by cysteamine administration. 611 61

Eighty-one primary ovarian carcinoids and intraovarian metastases from six mid-gut carcinoids were examined for the presence of tumor cells immunoreactive with antisera raised against various neurohormonal peptides, mostly of gastroenteropancreatic (GEP) origin. Twenty of the primary and two of the metastatic carcinoids contained such tumor cells. The incidence of tumors with any kind of neurohormonal peptide immunoreactive tumor cells was 53% in the trabecular carcinoids, and 42% in the strumal carcinoids, whereas the incidence was much lower (7%) in the insular type. Immunoreactive pancreatic polypeptide (PP), glucagon, enkephalin, and somatostatin were those neurohormonal peptides most commonly observed in the tumor cells of the primary carcinoids. Those less commonly found were substance P, calcitonin, VIP, neurotensin, beta-endorphin, and ACTH. Four metastatic carcinoids were nonreactive with all the antisera used. Cells storing immunoreactive insulin, glucagon, PP, VIP, gastrin, substance P, or enkephalin were found in one of the two remaining metastatic carcinoids; in the other only gastrin-immunoreactive tumor cells were observed. The occurrence and distribution of tumor cells storing the neurohormonal peptides in ovarian carcinoids are discussed in relation to their possible origin in the ovary and to carcinoids in the gut.
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PMID:Neurohormonal peptides in ovarian carcinoids: an immunohistochemical study of 81 primary carcinoids and of intraovarian metastases from six mid-gut carcinoids. 611 50

Activation of adenylate cyclase (AC) by PGE2, histamine and gastrointestinal hormones was studied in parietal cell-free gastric biopsy specimens from the corpus of patients with proven high gastrin achlorhydria. PGE2, somatostatin, VIP, pentagastrin and secretin activated AC in a concentration-dependent manner both in normal and in atrophic mucosa. Histamine activated AC only in normal gastric mucosa, being entirely ineffective in mucosa devoid of parietal cells. The results indicate that histamine-sensitive AC disappears in patients with achlorhydria, probably due to their loss of parietal cells. Enzyme activity in response to somatostatin, VIP, pentagastrin, secretin and PGE2 remains unchanged in these patients indicating AC localization in nonparietal cells, e.g. chief or mucous cells.
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PMID:Adenylate cyclase in gastric mucosal biopsies from patients with achlorhydria. Stimulation by PGE2, histamine and gastrointestinal hormones. 613 85

Regulation of pancreatic exocrine secretion is comprised of a complex interplay between hormonal and nervous mechanisms. Stimulatory gut hormones which act via the circulation include secretin, CCK, gastrin and bombesin, while VIP operates through peptidergic nervous release. Pancreatic polypeptide and glucagon are two examples of circulating inhibitory hormones while inhibition by somatostatin is through a paracrine release mechanism. Although the effects of vagal cholinergic nerves have been previously thought to be indirect through hormone release evidence is now accumulating for a direct role. Altered hormone release has been noted in chronic pancreatic insufficiency, cystic fibrosis and coeliac disease and may contribute in an important way to the pathophysiology of these malabsorptive disorders.
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PMID:Neuro-hormonal control of pancreatic function in man and its failure. 613 50

Recent investigations have shown that the functions of the gastrointestinal organs may be regulated by a complex system of paracrine cells and peptidergic nerves, in addition to the established humoral and autonomic nervous systems. In this article we discuss the possible paracrine regulation of the secretory functions of the stomach and the pancreas by somatostatin-producing D-cells. Secondly, we discuss the distribution, localization, effects and secretion of the neuropeptides VIP and 'gastrin-releasing polypeptide' (GRP or 'mammalian bombesin') applied to the stomach (GRP) and pancreas (GRP and VIP) of the pig. It is concluded, that all three peptides are capable of influencing powerfully the secretory state of these organs, and that these newer regulatory peptides probably play an important role in the integrate neurohormonal control of gastrointestinal secretion.
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PMID:Interrelation of nerves and hormones in stomach and pancreas. 613 53

Increasing numbers of peptides have been found in the gastrointestinal tract. Some of these are localized primarily in endocrine cells in the gastrointestinal epithelium (e.g., gastrin, secretin) or pancreatic islets (e.g., insulin, glucagon), and function chiefly as circulating hormones. Other peptides, e.g., VIP, are principally neuropeptides present mainly in nerve cells, nerve fibres and nerve terminals; they function mainly as neurotransmitters or neuromodulators. The isolation of gut peptides has usually depended on the use of characteristic bioassays. More recently, some peptides have been isolated on the basis of unique terminal amino-acid composition. Certain chemical structures are associated with typical biological actions, and several "families" of related peptides are recognized.
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PMID:Isolation, localization, and characterization of gastrointestinal peptides. 614 28

Blood samples were collected in peripheral venous blood of seven lactating sows, when their piglets were suckling. In four of the experiments samples were also taken when the sows were fed a meal. Gastrin, insulin, somatostatin and VIP levels were measured by radioimmunoassay. Insulin levels increased by approximately 100% for about 10 min in response to suckling, in some experiments even before the suckling occurred, i.e. when the sows saw, heard and smelled their piglets. In four of the sows suckling caused a biphasic twofold increase in gastrin levels - one immediate peak which lasted for a few min and a second peak of longer duration (about 30-60 min), whereas gastrin levels remained unchanged in three animals. Somatostatin levels usually reflected gastrin levels in a reciprocal way. Thus, a biphasic decrease of somatostatin levels occurred in the high gastrin responders. In contrast, somatostatin levels increased in the experiments, in which gastrin levels did not change. Immediate and short-lasting (a few minutes long) increases of VIP levels were also induced by suckling. Large litters and long suckling periods appeared to be related to greater changes of the levels of all the peptides measured. Feeding influenced insulin, gastrin and somatostatin levels in the same way as did suckling from both a qualitative and a quantitative point of view. In contrast, VIP levels were not increased by feeding. The possible functional effects of the suckling-induced release of gastrointestinal hormones and possible mechanisms of their release are discussed.
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PMID:Influence of suckling and feeding on insulin, gastrin, somatostatin and VIP levels in peripheral venous blood of lactating sows. 614 43

Immunological and biological studies have shown that many of the mammalian gastroenteropancreatic (GEP) hormones have counterparts in lower vertebrates. Hormonal localization in cyclostomes and fishes suggests that insulin was phylogenetically the first islet hormone, followed by somatostatin, glucagon and, last, pancreatic polypeptide (PP). Some of the GEP peptides are present in the central and peripheral nervous system of lower vertebrates as well as mammals. GEP hormone-like substances resembling insulin, somatostatin, glucagon, PP, gastrin, secretin, VIP, substance P and enkephalin also occur in protostomian invertebrates (Annelida, Arthropoda, Mollusca), particularly in their nervous system. These findings indicate that the vertebrate hormones may have originated in neural tissue before the development of the vertebrate line of evolution.
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PMID:Gut-islet endocrinology-some evolutionary aspects. 615 46

In the Lausanne classification of islet cells which is based mainly on the ultrastructural characteristics of secretion granules, a total of nine different cell types have been described. By immunocytochemistry at least 12 different hormones or peptides have been either detected or postulated as being within cell types in the pancreatic islets. The cells responsible for the secretion of insulin, glucagon, GIP, pancreatic polypeptide and somatostatin have been firmly established. The identification of cells containing VIP, secretin, gastrin, biogenic amines and other peptides still remain tentative. The development of immunocytochemical techniques and their use at the light microscopic and ultrastructural level have been of immense value in the recognition of islet cell types and the peptides that they contain. Continued improvement in the purification of islet hormones and specific antibodies to these hormones together with correlative and immunocytochemical studies should lead to a better understanding of normal islet cell function, and thus hopefully, the cellular abnormalities encountered in tumors of the endocrine pancreas.
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PMID:Types of pancreatic islet cells and their immunocytochemical identification. 616 78

Using rabbit and guinea-pig antisera, raised against GEP neurohormonal peptides of mammalian origin, cells were observed in the brain and/or in the fused ventral ganglia of the last (fifth) larval instar of the hoverfly, Eristalis aeneus, being immunoreactive with antisera against insulin, somatostatin, glucagon, PP, secretin, gastrin/CCK/caerulein; substance P, enkephalin and endorphin. Most of these GEP neurohormonal peptides also occurred in nerve fibers. No immunoreactive cells or nerve fibers could be detected with antisera against GIP, VIP, (the central fragments of) CCK, bombesin or neurotensin. The antisera tested failed to reveal any immunoreactive cells or nerves in Weismann's ring (fused corpus allatum/corpus cardiacum and thoracic gland) or in different parts of the alimentary tract. The observations support the hypothesis that neuronal GEP hormonal peptide production in the brain is a genuinely original mechanism and the appearance of endocrine cells in the gut a later feature in evolution.
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PMID:Immunohistochemical evidence of gastro-entero-pancreatic neurohormonal peptides of vertebrate type in the nervous system of the larva of a dipteran insect, the hoverfly, Eristalis aeneus. 616 52


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