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)

Cholecystokinin (CCK)-like immunoreactivity (CCK-LI) in a pool of 12 dog brains was extracted sequentially into boiling water and cold 2% trifluoroacetic acid. Gel filtration on Sephadex G-50 revealed three main molecular forms detected by a carboxyl-terminal antibody; one was eluted in the position of CCK-58 (58 amino acid residues long); a second, in the position of CCK-8; and a third, near the radioactive iodide marker. When the CCK-LI was purified by affinity chromatography using carboxyl-terminal CCK antibody followed by three steps of reversed-phase high-pressure liquid chromatography, three components were isolated and characterized by sequence microanalysis. The smallest component was the pentapeptide common to gastrin and CCK. The second peak was eluted in the same region as synthetic CCK octapeptide, and sequence analysis showed that the chemical structure of this biologically active region of canine CCK is identical to that found in sheep and pig brains. The 22-residue amino-terminal sequence of brain CCK-58 was: Ala-Val-Gln-Lys-Val-Asp-Gly-Glu-Pro-Arg-Ala-His-Leu-Gly -Ala-Leu-leu-Ala-Arg-Tyr-Ile-Gln-, the same as the sequence found for canine intestinal CCK-58 from this pool of dogs. This is the same sequence others have reported for porcine brain CCK-58 lacking nine amino acid residues (CCK-58 desnonapeptide) except that the porcine peptide had a serine in position 9. The canine CCK amino-terminal sequence differed from the sequence Ala-Gln-Lys-Val-Asn-Ser previously reported for intestinal CCK-58 purified from another pool of dog tissue, but the rest of the residues identified were identical in the two peptides. CCK-58 may be a molecular precursor of the smaller forms of CCK in brain as well as in gut.
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PMID:Isolation of a large cholecystokinin precursor from canine brain. 609 6

The decapeptide form of human gastrin releasing peptide was isolated from acid extracts of liver tissue containing a metastatic human bronchial carcinoid tumor. A larger form also was isolated and partially characterized. During gel permeation chromatography the major immunoreactive peak eluted in the same region as synthetic gastrin releasing decapeptide while a second minor immunoreactive peak eluted near gastrin releasing peptide. Bombesin-like immunoreactivity (BLI) was purified by successive applications to reverse phase high pressure liquid chromatography (HPLC) columns. After four successive HPLC purifications a single peak of bombesin-like immunoreactivity was detected. Amino acid analysis, microsequence analysis and coelution with synthetic peptide indicated that the predominant form present in metastatic tumor tissue was identical to the decapeptide form of canine gastrin-releasing peptide. The less abundant form was purified by cation exchange chromatography followed by reverse phase high pressure liquid chromatography. Partial microsequence analysis of this peptide, through the first 11 residues, was Val-Pro-Leu-Pro-Ala-Gly-Gly-Gly-Thr-Val-Leu. This sequence differed from that of hog heptacosapeptide gastrin releasing peptide at positions 1,3,4 and 5 and from the canine peptide as positions 1,3,5, and 7.
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PMID:Isolation and sequence analysis of human bombesin-like peptides. 609 16

The hypoglycaemia of infantile hyperinsulinism is often exceedingly difficult to control. The use of somatostatin has been advocated recently in such infants because of its effect on inhibiting insulin release, but nothing is known of the wider effects of this potent hormone in the young child. Two infants presenting at 9 weeks and 5 days of age with severe hyperinsulinaemic hypoglycaemia were studied during an infusion of somatostatin. In both infants normoglycaemia was restored with suppression of insulin secretion. An increase in blood ketone bodies occurred, but no change was seen in blood pyruvate, lactate or alanine concentrations. The plasma concentrations of glucagon, cortisol, growth hormone, motilin, pancreatic polypeptide, gastric inhibitory of polypeptide, neurotensin, gastrin and vasoactive intestinal peptide decreased markedly during the somatostatin infusion. No consistent change occurred in plasma enteroglucagon or secretin values. We conclude that somatostatin effectively suppresses abnormal insulin secretion in infants, but it has profound effects on the release of nine other hormones. Further studies are needed to define the consequences of suppressing the release of these hormones before somatostatin can be used routinely in the management of infantile hyperinsulinism.
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PMID:Effect of somatostatin infusion on intermediary metabolism and entero-insular hormone release in infants with hyperinsulinaemic hypoglycaemia. 611 71

Within the physiological range of other known releasing factors, human pancreatic tumor growth hormone releasing factor (hpGRF) is specific for GH release. Data concerning hpGRF action on cAMP and GH are consistent with the concept of cAMP acting as a second messenger for this releasing factor. hpGRF-stimulated GH release is Ca++ dependent. Exogenous hpGRF40 does not alter the interdigestive gastric motility or secretion of gastrin and motilin in dogs, while large doses of hpGRF stimulate somatostatin release into the hepatic portal blood of the rat. Significant GRF activity as determined by a rat pituitary perifusion system is confined within the median eminence and the arcuate nucleus, though detectable but insignificant GRF activity is present in other area of the hypothalamus and cortex in the rat. GRF activity is present in the ovine brain as well as in the gut. Both tissues contain large (between 4000-5000 daltons) and small (but possibly larger than 1000 daltons) m.w. GRF materials. GRF appears to be structurally different between species and more than one GRF may be present within the same species. One of the ovine brain peptides with GH-releasing activity was partially characterized as His-Ser-Asp-Gly-Ile-Phe-Thr-Asp-Ser-Tyr- Lys-Arg-Try-Asn-Lys-Glu-Met- Ala-Lys--which is similar to rat GRF and porcine VIP having His at the N-terminus. Another peptide with GRF activity which eluted earlier on reverse phase HPLC and later on cation exchange chromatography has also been obtained in a pure form.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Growth hormone releasing factors in the brain and the gut: chemistry, actions, and localization. 620 12

From a side fraction obtained in our previous isolation of neuromedin B from porcine spinal cord, we have purified another decapeptide that exhibits a potent stimulant effect on the smooth muscle preparation of rat uterus. By microsequencing and synthesis, the amino acid sequence of the peptide has been identified as: Gly-Asn-His-Trp-Ala-Val-Gly-His-Leu-Met-NH2. This peptide is found to be identical with the carboxy-terminal subsequence [18-27] of gastrin releasing peptide, and to display a potent contractile activity on rat uterus in the characteristic manner of bombesin. These facts strongly suggest that the peptide may be a neuromediator in the neural communication systems of mammals. We propose the name "neuromedin C" for this peptide, since it is closely related to "neuromedin B", recently identified as a bombesin-like mammalian peptide.
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PMID:Neuromedin C: a bombesin-like peptide identified in porcine spinal cord. 654 86

The effects of an amino acid derivative (N-benzoyl-L-argininamide), four small peptides (Phe-Gly-Phe-Gly, gastrin-related peptide (Trp-Met-Arg-Phe-NH2), tetragastrin (Trp-Met-Asp-Phe-NH2), pentagastrin (Boc-beta Ala-Trp-Met-Asp-Phe-NH2] and one medium-sized peptide, glucagon (29 residues), on the gel-to-liquid crystalline transition of a multilamellar suspension of dimyristoylphosphatidylcholine have been studied by means of high-sensitivity differential scanning calorimetry. At low concentrations of added solutes, the temperature at which the excess apparent specific heat in the gel-to-liquid crystalline phase transition of the lipid is maximal is lowered by an amount proportional to the total concentration of the peptide, with proportionality constants ranging from -0.018 K mM-1 for Phe-Gly-Phe-Gly to -3.1 K mM-1 for the gastrin-related peptide. The lipid mixtures involving the first two solutes listed above exhibited approximately symmetrical curves of excess apparent specific heat vs. temperature. The curves for the other solutes were asymmetric, and could be well represented as the sum of either two or three two-state curves. The asymmetry, which was especially pronounced in the cases of pentagastrin and glucagon, thus appeared to be due to the presence of components having lower and/or higher transition temperatures than that of the lipid. Pentagastrin and glucagon (R.M. Epand and J.M. Sturtevant, Biochemistry 20 (1981) 4603) have much smaller effects on the gel-to-liquid crystalline phase transition of dipalmitoylphosphatidylcholine than on that of the dimyristoyl analog.
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PMID:The effects of various peptides on the thermotropic properties of phosphatidylcholine bilayers. 654 24

Pancreatic polypeptide was infused intravenously in healthy fasting subjects at 1 pmol kg-1 (n = 7) and 4 pmol kg-1 min-1 (n = 10) producing plasma PP concentrations of 223 +/- 37 pmol/l (mean +/- SEM) and 891 +/- 64 pmol/l respectively. These levels are similar to and four-fold higher than those seen after a normal mixed breakfast in healthy young adults. In a separate study five healthy subjects ingested a small breakfast during infusion of PP on different days at 1 pmol kg-1 min-1 and 2 pmol kg-1 min-1 respectively. PP at 1 pmol kg-1 min-1 caused a marked reduction in fasting plasma motilin concentrations to 20% of the basal level (p less than 0.001). There were, however, no significant changes in plasma concentrations of insulin, glucagon, gastrin, secretin, enteroglucagon, gastric inhibitory peptide or neurotensin. Despite previous reports possibly implicating PP in metabolism, there were no significant effects on blood levels of glucose, alanine lactate, 3-hydroxybutyrate, glycerol or non-esterified fatty acids, either in the fasting state or after the ingestion of food. Although it seems unlikely that PP is a major hormonal regulator of intermediary metabolism in man, its ability to suppress motilin at physiological concentrations suggests the possibility of an indirect influence on digestive motor function.
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PMID:Effects of pancreatic polypeptide on motilin and circulating metabolites in man. 678 20

The pH dependence of circular dichroism spectra has been studied for dodecyl sulfate complexes formed by 25 proteins and for a random copolypeptide of glutamic acid and alanine. The pH range covered is that in which titration of side-chain carboxyl groups is to be expected. Circular dichroism spectra signify an increase in helical content upon acidification, although in many cases the increase is quite small. For all but three of the proteins studied, the spectral changes are in reasonable agreement with those expected because helix propagation by glutamyl and aspartyl residues is enhanced when the state of the side-chain carboxyl changes from COO- to COOH. This simple explanation seriously underestimates conformational changes reported for gastrin, Kunitz trypsin inhibitor and tropomyosin. Changes in charge density appear to play an important role in these proteins.
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PMID:Helix formation upon acidification of protein-dodecyl sulfate complexes. 682 4

Plasma enteroglucagon, pancreatic polypeptide, gastrin, motilin, neurotensin, gastric inhibitory polypeptide, secretin, vasoactive intestinal peptide and blood glucose, alanine, ketone bodies, lactate and pyruvate were measured on the sixth postnatal day in (a) a group of 10 preterm infants who on account of hyaline membrane disease had not received enteral feeding since birth and (b) before and at 55, 90, and 120 minutes after feeding in a group of healthy preterm infants fed three-hourly on human milk. Gut hormones were also measured in umbilical venous cord blood. The infants receiving regular boluses of milk from birth demonstrated postnatal surges in preprandial concentrations of gut hormones together with cyclical hormonal responses to feeding. None of these changes were seen in infants receiving intravenous fluids. The latter infants also had lower concentrations of blood alanine, glycerol and hydroxybutyrate and lacked the phasic changes in intermediary metabolites seen in the infants receiving enteral boluses of milk. Thus deprivation of enteral feeding results in a profound alteration of the metabolic and endocrine milieu which may have important effect on the process of adaptation to postnatal life.
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PMID:Metabolic and endocrine consequences of depriving preterm infants of enteral nutrition. 683 98

To determine whether intravenous infusion of individual amino acids stimulated gastric acid secretion in man, graded doses of phenylalanine, tryptophan, glycine, alanine, histidine, and NaCl control were infused on separate days in nine healthy subjects. Intravenous infusion of phenylalanine and tryptophan significantly stimulated gastric acid secretion to 50 and 52%, respectively, of the acid secretory response to intragastric peptone. Intravenous alanine and histidine were without effect, whereas glycine produced a slight response. Serum gastrin concentrations did not significantly change during intravenous amino acid infusion, except in response to 0.1 M phenylalanine. However, the increase in serum gastrin occurred 2 h after acid secretion had significantly increased in response to the 0.025 M phenylalanine infusion. Plasma amino acid concentrations were measured during intravenous amino acid infusion and in response to a steak meal in five of the subjects. At a time when acid secretion was significantly increased during intravenous infusion of phenylalanine and tryptophan, plasma amino acids were similar to, or less than, that observed after the steak meal, suggesting that circulating levels of these three amino acids have a physiologic effect on gastric secretion in man. Intravenous infusion of a combination of graded doses of phenylalanine plus a continuous infusion of 0.01 M tryptophan shifted the dose-response curve to the left and resulted in a significantly greater response than to either amino acid alone. In five subjects with parietal cell vagotomy, intravenous phenylalanine and tryptophan stimulated acid secretion, whereas histidine was without effect, similar to normal subjects. These studies indicate that intravenous infusion of small amounts of phenylalanine (0.025 M, 3.1 mmol/h) and tryptophan (0.01 M, 1.25 mmol/h) stimulated gastric acid secretion at plasma concentrations similar to those observed after a steak meal, suggesting a physiologic role for circulating levels of these amino acids on gastric acid secretion. Because acid secretion increased at a time when serum gastrin was unchanged and since there was no correlation between changes in serum gastrin and acid secretion, the responses to phenylalanine and tryptophan are probably mediated by a nongastrin-related mechanism(s). Since both phenylalanine and tryptophan stimulated secretion in vagotomized subjects, the response is vagally independent. These observations suggest that circulating levels of these two amino acids have either a direct or indirect effect on or near the human parietal cell.
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PMID:Intravenous infusion of L-isomers of phenylalanine and tryptophan stimulate gastric acid secretion at physiologic plasma concentrations in normal subjects and after parietal cell vagotomy. 685 13


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