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)

The previously described peptide material that reacts with antibodies to gastrin and is found in the central nervous system of various vertebrates is present in only the 100,000 X g pellet of postmortem human cerebral cortical grey matter. This immunoreactive material, extractable in boiling water, is biologically active on rat pancreatic preparations. On the basis of size, charge, immunological specificity, and patterns of biological activity, most of this material is closely related to the COOH-terminal octapeptide of cholecystokinin in its complete, sulfated biologically active form.
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PMID:Demonstration of biological activity of brain gastrin-like peptidic material in the human: its relationship with the COOH-terminal octapeptide of cholecystokinin. 27 70

Circulatory effects of gastrointestinal hormones and related peptides are surveyed. Only experiments using low peptide dosages, non-extensive surgery and intravenous infusions give relevant data in this field. Glucagon, secretin, vasoactive intestinal peptide, gastrin, cholecystokinin, Substance P and Somatostatin are vasoactive within the splanchnic area, each fraction in a specific pattern.
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PMID:Circulatory effects of gastrointestinal hormones and related peptides. 27 37

An enzyme has been partially purified from canine and porcine cerebral cortical extracts that differs from trypsin in that it manifests some degree of hormone specificity since it converts porcine cholecystokinin to smaller immunoreactive forms, i.e., the COOH-terminal dodecapeptide and octapeptide fragments, but fails to convert big gastrin (34 amino acids) to heptadecapeptide gastrin. This enzyme is distinguishable from trypsin not only in substrate specificity, but also in several physiochemical properties. It is not inhibited in the presence of concentrations of lima bean trypsin inhibitor sufficient to inhibit 1 mg of trypsin per ml of incubation mixture. It is inactivated when incubated with substrate at 45 degrees C for 1 hr, whereas trypsin remains fully active when incubated under the same conditions at 55 degrees C. The enzyme elutes in the void volume on Sephadex G-50 and G-75 gel filtration. On sucrose gradient centrifugation, the proteolytic activity associated with trypsin is recovered above albumin but that of the solubilized brain enzyme is recovered below gamma globulin. The enzyme is not detectable in splenic extracts, which do contain nonspecific proteases capable of completely degrading cholecystokinin. Further investigation is required to determine whether the enzyme in the gut that converts cholecystokinin to the bioactive and immunoactive COOH-terminal fragments resembles or is different from the brain converting enzyme.
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PMID:Characterization of a nontrypsin cholecystokinin converting enzyme in mammalian brain. 28 18

In vitro duodenal muscle was found to be a useful tool in the study of natural compounds. In the field of polypeptides rat duodenum was found to be of definite importance to differentiate the bradykinins (which induce relaxation) from the tachykinins (which evoke contractions). Human duodenum both "in vitro" and "in vivo" is relaxed by peptides of the gastrin and cholecystokinin family (like caerulein), whereas it is contracted by bombesin. Dog and cat duodenum is contracted by all the different types of peptides though in various degrees. Guinea pig duodenum is contracted by many peptides and also by histamine and related substances. In this case another differentiation seems to be possible as contraction induced by stimulation of H1 receptors concerns essentially the longitudinal muscle layer whereas stimulation of H2 receptors seems to inhibit the longitudinal contraction because of a contraction of the circular muscle or because of true relaxation of the longitudinal muscle. All the above considerations suggest that a comparative study performed on duodenal muscle of different animals might give useful information in the screening of new natural active compounds of synthetic analogues.
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PMID:"In vitro" duodenal muscle in the pharmacological study on natural compounds. 29 13

Permanent semi-microelectrodes were implanted in the ventromedial hypothalamus (VMH), lateral hypothalamus (LH), amygdala (AMYG), medial forebrain bundle (MFB), anterior hypothalamus (AH), inferior colliculus (IC), and caudate nucleus (CN). Average evoked responses were recorded simultaneously from the above sites in freely behaving rats before and after administration of pentagastrin (100 microgram/kg), secretin 1 microgram/kg or cholecystokinin octapeptide (CCK-OP) (1 microgram/kg) in search of satiety signal. Gastrin and secretin had little effect while it appears that CCK may perform a regulatory function in a neurohumoral feedback mechanism.
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PMID:Endocrine control of appetite: gastrointestinal hormonal effects on CNS appetitive structures. 30 89

The neurotensin-cell is identified immunohistochemically and ultrastructurally by differential counting of endocrine cells in the gut of a primate (Tupaia belangeri). Utilizing light microscopy, the EC-cells are identified by the Masson-Fontana silver stain; with the same method the neurotensin cells are not stained. The other endocrine cells have been quantified in the small intestine using the peroxidase-antiperoxidase stain with antisera against glucagon, somatostatin, cholecystokinin, gastrin, secretin, pancreatic polypeptide, gastric inhibitory peptide and neurotensin. In the ileal mucosa of Tupaia, the most frequent endocrine cell is the EC-cell followed by the glucagonoid cell, (L-cell). The immunoreactive neurotensin cell represents the third most frequent endocrine cell in this region. On the ultrastructural level, this third most frequent endocrine cell is a heretofore undescribed cell, the N-cell, containing electron dense secretory granules measuring 335 +/- 87 nm in diameter.
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PMID:Ultrastructural identification of a new cell type--the N-cell as the source of neurotensin in the gut mucosa. 33 60

This is a review of current information concerning the role of hormones and the autonomic nervous system in the control of exocrine secretions of the pancreas. A greater emphasis has been placed on the role of hormones because of information accumulated during the last several years. With the development of radioimmunoassay techniques, it is now possible to correlate circulating hormone concentrations with biological function. The role of hormones has been discussed with the framework of the secretin-glucagon family, the cholecystokinin-gastrin family, and other proposed gastrointestinal hormones and related peptides. Gastrin, secretin and cholecystokinin-pancreozymin are three prime gut hormones that regulate pancreatic secretion. Other hormones that may have a role in pancreatic secretion include glucagon, vasoactive intestinal polypeptide, chymodenin, somatostatin, pancreatic polypeptide, motilin, and bombesin. Neural mechanisms play an important although not so succinct a role in the over-all control of exocrine secretion. A complex relationship exists between the parasympathetic nervous system and the release of the hormones and their effect on pancreatic acinar and duct cells.
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PMID:Neurohormonal control of pancreatic secretion. A review. 34 Mar 22

The development of cytodifferentiation of endocrine cells that produce the gastrointestinal hormones gastrin, cholecystokinin and secretin have been studied by a combined fluorescence-cytochemical, immunocytochemical and ultrastructural approach. The results show that, during development, several ultrastructurally distinct cell types exhibit COOH-terminal gastrin and cholecystokinin immunoreactivity. Furthermore, some cells simultaneously contain both gastrin- and cholecystokinin-specific antigenic determinants. Studies on the time course of development of gastrin and cholecystokinin cells, together with the above-mentioned data, suggest that gastrin cells may be converted into cholecystokinin cells in development. During this period, gastrin, cholecystokinin and secretin cells store the biogenic monoamine, 5-hydroxytryptamine a feature not displayed by the adult counter-parts of these cells. In the adult duodenum, characteristic enterochromaffin (EC) cells store 5-hydroxytryptamin for which, evidence for a possible hormonal role has been presented. Taken together, our data indicate that the differentiation of duodenal endocrine cells occurs in distinct steps, each involving a restriction in the biosynthetic repertoire of the cell.
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PMID:Ultrastructural and cytochemical studies on the cytodifferentiation of duodenal endocrine cells. 36 73

Gastrin and cholecystokinin (CCH) cells of the rat gastrointestinal tract have been studied by immunocytochemistry and radioimmunoanalysis. With antisera directed against the COOH-terminal tetrapeptide sequence, which is common to gastrin and CCK, three distinct endocrine cell types are detected. One of the cell types predominates in the antrum, is scarce in the rest of the gut and corresponds to the gastrin cell. The second cell type is virtually confined to the duodenum and jejunum and corresponds to the CCK cell. The third cell type occurs disseminated in the small intestines, predominates in the ileum, and reacts with COOH-terminus-specific antisera only following diethylpyrocarbonate and not following formaldehyde fixation. It is possible that the third cell type stores a third member of the gastrin-CCK family of gut hormones.
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PMID:Distribution of gastrin and CCK cells in the rat gastrointestinal tract. Evidence for the occurrence of three distinct cell types storing COOH-terminal gastrin immunoreactivity. 36 36

To examine gut-islet interrelationships, we entirely separated the gastrointestinal tract from the rat. When we arterially perfused this preparation with an erythrocyte-free solution for 1 h, it remained histologically intact and took up oxygen and glucose. Feedings were given via a duodenal tube. The gut absorbed glucose when glucose in the feeding was high (9.2 g/dl), but not when glucose in the feeding was low (58 mg/dl). With feeding, the portal venous effluent (PVE) from this preparation (stomach to ileum) enhanced late-phase, glucose-induced insulin secretion from pancreas of another rat. This enhancement occurred when the gut was fed either glucose (9.2 g/dl) in electrolyte solution or electrolyte solution alone. PVE from glucose-fed upper gut (stomach, duodenum) was similarly insulinotropic. In contrast, PVE from unfed gut or from glucose-fed gut of old rats was not insulinotropic. PVE from all gut preparations except upper gut produced a glucagon "spike" during basal pancreatic perfusion. Effects of gastrointestinal peptides (gastric inhibitory polypeptide, cholecystokinin octapeptide, secretin, gastrin) and immunoassays of PVE suggested that the insulinotropic substance is not one of these peptides. Thus, an insulinotropic substance that is not dependent on feeding nutrient material is secreted from the intestine.
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PMID:Secretion of an insulinotropic factor from isolated, perfused rat intestine. 37 52


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