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 effects of substance P, eledoisin and physalaemin--which are structurally similar and all belong to the tachykinin family--and of bombesin, a gastrin-releasing peptide, on non-pyramidal neurones were studied using unitary extracellular recordings from rat hippocampal slices. The peptides were added to the perifusion solution, or locally applied by pressure ejection from a micropipette, at concentrations ranging from 10(-8) to 10(-6) M. 104 out of 115 non-pyramidal neurones responded to tachykinins, and 26 out of 27 responded to bombesin, by a reversible, concentration-dependent increase in firing. The responsive neurones retained their sensitivity to the tachykinins and to bombesin under the condition of synaptic blockade. A synthetic peptide known to antagonize the effects of oxytocin on hippocampal non-pyramidal neurones did not affect the excitations induced by the tachykinins or bombesin. The action of the tachykinins was not blocked by the muscarinic antagonist, atropine. These results indicate that hippocampal non-pyramidal neurones--which were previously shown to possess oxytocin receptors and mu-type opiate receptors--bear receptors for peptides of the tachykinin and of the gastrin-releasing families. The hippocampal effects of tachykinins and of bombesin, however, were not blocked by synthetic structural analogues of substance P, known to antagonize the action of these peptides on some non-nervous tissues. The possibility must be considered that brain receptors for tachykinins and for gastrin-releasing peptides may be distinct from the peripheral receptors for these peptides.
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PMID:Tachykinins and bombesin excite non-pyramidal neurones in rat hippocampus. 243 94

We extracted gastrin-releasing peptide (GRP) and its C-terminal decapeptide corresponding to 6.4 and 6.8 pmol/g from pig antrum mucosa. By immunohistochemistry GRP was localized to mucosal, submucosal, and myenteric nerve fibers. A few nerve cell bodies were also identified. Using isolated perfused pig antrum with intact vagal innervation, we found concomitant, atropine-resistant release of GRP and gastrin during electrical stimulation of the vagal nerves. Intra-arterial GRP at 10(-11)-10(-10) mol/l caused up to fivefold, dose-dependent increases in gastrin secretion; higher doses were less effective and completely desensitized the gastrin cells for the lower doses. After desensitization, vagal stimulation no longer produced gastrin secretion. The substance P antagonist [D-Arg, D-Pro, D-Trp, Leu]-substance P, described as also antagonizing the actions of bombesin, decreased the gastrin response to GRP and abolished the effect of vagal stimulation. The available evidence strongly suggests that GRP nerves are responsible for the stimulatory vagal effects on gastrin secretion in the pig.
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PMID:GRP nerves in pig antrum: role of GRP in vagal control of gastrin secretion. 244 6

We have studied the effect of gastrin-releasing peptide (GRP) on exocrine and endocrine secretion in the totally isolated, vascularly perfused rat stomach with or without concomitant infusion of a potent somatostatin antiserum. GRP (1 nM) showed a marginal acid-stimulatory effect (base line, 11.6 +/- 2.3 mumol/60 min, and after GRP, 20.0 +/- 2.2 mumol/60 min; p = 0.05). GRP significantly increased gastrin and somatostatin release to the venous effluent, and the venous gastrin concentration increased significantly during concomitant infusion of somatostatin antiserum. Furthermore, GRP inhibited histamine liberation, and somatostatin antiserum reversed this effect. The antiserum did not significantly stimulate acid secretion. Thus, the present study shows that GRP directly or indirectly affects both acid secretion and the release of gastrin, somatostatin, and histamine in the rat stomach.
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PMID:The effect of gastrin-releasing peptide on acid secretion and the release of gastrin, somatostatin, and histamine in the totally isolated, vascularly perfused rat stomach. 246 48

Nervous and endocrine peptidergic structures in human Brunner's glands were studied by immunofluorescence. Endocrine cells storing immunoreactive components respectively similar to somatostatin 14, the amino-terminal portion (1-14) of somatostatin 28, gastrin-cholecystokinin, and peptide YY were distributed throughout the acini. Peptidergic nerve structures contained materials immunologically related to vasoactive intestinal peptide, peptide histidine methionine, substance P, neuropeptide Y, and gastrin-releasing peptide. The latter peptide was detected in discrete fibers running into the acini but within no cell body in the submucosa. All other neuropeptides were stored in fibers, isolated or grouped in bundles, and in perikarya of submucosal ganglia close to the acini. No immunoreactive structures were detected using antisera directed against pancreatic polypeptide, secretin, motilin, neurotensin, or calcitonin gene-related peptide. The results suggest that several regulatory peptides may be involved in the control of Brunner's glands in humans.
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PMID:Immunocytochemical study of peptidergic structures in Brunner's glands. 247 87

Concentrations of regulatory peptides in an extract of the intestine of the cyclostome, Myxine glutinosa (Atlantic hagfish), were measured by radioimmunoassay using 12 antisera of defined regional specificity that were raised against mammalian gastrointestinal peptides. The hagfish gut contained somatostatin-, cholecystokinin/gastrin-, C-terminal substance P-, and neurokinin A-like immunoreactivity in concentrations that were 10 to 100 times less than the corresponding concentrations in the rat intestine. The hagfish gut also contained glucagon-like immunoreactivity, measured with both C- and N-terminally directed antisera, but the immunoreactivity did not dilute in parallel with the porcine glucagon standard in radio-immunoassay. No immunoreactivity was detected using antisera to calcitonin gene-related peptide, gastrin-releasing peptide, neuromedin U, neurotensin, N-terminal substance P, and vasoactive intestinal polypeptide. The somatostatin-like immunoreactivity in the hagfish gut was resolved by HPLC into components with the retention times of somatostatin-34 and somatostatin-14, previously isolated from the hagfish islet organ (relative abundance 2:1). The retention times of hagfish glucagon and of the multiple molecular forms of the tachykinin-like peptides were appreciably different from the retention times of the corresponding mammalian peptides.
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PMID:Neurohormonal peptides in the gut of the Atlantic hagfish (Myxine glutinosa) detected using antisera raised against mammalian regulatory peptides. 248 Feb 67

This study investigated the effects of two putative bombesin antagonists, [D-Arg1,D-Pro2,D-Trp7,9,Leu11]substance P and [Leu13-psi-CH2NH-Leu14]bombesin, on bombesin-stimulated gastrin release from isolated canine G cells following short-term culture. Canine antral tissue was dispersed by sequential collagenase and EDTA treatment, and counterflow elutriation was used to enrich for G cells. Plates were seeded with 2 x 10(6) cells/mL in each well and cultured for 2 days prior to testing. Gastrin-containing and somatostatin-containing cells were identified by immunocytochemistry using the biotin-avidin-peroxidase method and accounted for 8.5 and 1%, respectively, of adhered cells. Basal gastrin secretion was 1.91 +/- 0.48% of total cell content. After a 2-h incubation period, bombesin (0.01-100 pM) stimulated gastrin release in a concentration-dependent fashion. The substance P analog, at a concentration of 1 microM, modestly inhibited bombesin-stimulated gastrin release from canine G cells. This analog also produced weak stimulation of basal gastrin release. In contrast, the bombesin analog, at a concentration of 1 microM, did not affect basal gastrin secretion. The bombesin analog completely blocked bombesin-stimulated gastrin release from 0.01 to 1 pM and produced greater than 50% inhibition at higher doses. The ability of the bombesin analog to directly inhibit bombesin-stimulated gastrin release from cultured canine G cells underscores its usefulness in studies involving the role of bombesin and its mammalian counterpart, gastrin-releasing peptide, in the control of gastrin cell function.
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PMID:Inhibition of bombesin-stimulated gastrin release from isolated canine G cells by bombesin antagonists. 248 58

Products of the gastrin-releasing peptide gene were isolated from culture medium supernatant of a small cell lung cancer line, NCI-H345, by several (high performance liquid chromatography) HPLC steps. The column eluates were monitored by immunoassay and absorbance profiles. Gastrin-releasing peptide was identified in HPLC eluates by a specific radioimmunoassay. Two carboxyl-terminal gastrin-releasing peptide gene-associated peptides were identified by a radioimmunoassay specific for their predicted carboxyl terminus. The amino termini of these two peptides were determined by microsequence analysis. The shorter peptide was revealed to be a fragment of the larger peptide. Expression of an alternate mRNA was shown by isolation and characterization of a novel tetradecapeptide. Amino acid analysis, microsequence analysis, and mass spectral analysis confirmed that the structure was Ser-Leu-Leu-Gln-Val-Leu-Asn-Val-Lys-Glu-Gly-Thr-Pro-Ser. This peptide represents the carboxyl terminus of a peptide resulting from alternate processing of gastrin releasing peptide mRNA. This mRNA contains a 19-base deletion, creating a frame shift. A radioiodinated synthetic analog of this peptide (Tyr-Leu-Val-Asp-Ser-Leu-Leu-Gln-Val-Leu-Asn-Val-Lys-Glu-Gly-Thr-Pro-Ser ) bound specifically to a small cell cancer line with high affinity, suggesting possible biological activity of the isolated peptide.
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PMID:Multiple gastrin-releasing peptide gene-associated peptides are produced by a human small cell lung cancer line. 253 94

Many small-cell lung cancers (SCLCs) produce gastrin-releasing peptides (GRPs) (mammalian bombesin) but the plasma concentration of GRP is rarely elevated, possibly because of its rapid elimination. We developed a radioimmunoassay for the C-terminal flanking peptide of proGRP and measured its concentration in plasma from 71 patients with SCLC, in 27 healthy subjects and in 49 patients with other diseases including lung carcinomas. In addition, we studied the molecular size of immunoreactive C-flanking peptide in two SCLC cell lines and in plasma from SCLC patients. The concentration of immunoreactive C-flanking peptide in normal subjects and in control patients did not exceed 10 pmol/L and 26 pmol/L, whereas 72% of the SCLC patients had C-flanking peptide concentrations above 10 pmol/L. In patients with extensive disease (n = 35) the median concentration was 71 pmol/L (range, 10 to 940). ProGRP C-flanking peptide levels paralleled the clinical course in 12 patients. The molecule(s) responsible for the immunoreactivity had a molecular size of about 8 to 10 kd in both patient plasma and tumor cell lines, suggesting that the measured peptide(s) represented major fragment(s) if not the entire C-flanking peptide of proGRP. Thus this peptide(s) seems to be a useful marker for SCLC.
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PMID:Elevated plasma concentrations of C-flanking gastrin-releasing peptide in small-cell lung cancer. 255 50

Prealbumin, one of the main thyroxine transport proteins, has recently been shown to be a valuable immunohistochemical marker of neuroendocrine tumours. We report the case of a multisecretory pancreatic endocrine tumour whose prealbumin secretion was so high that it produced a peak on routine serum protein electrophoresis and induced a euthyroid hyperthyroxinemia. The maximal binding capacity of prealbumin for thyroxine was indeed markedly increased, whereas its affinity for this hormone was normal. The tumour was associated with gastric hyperacidity and hypergastrinemia thereby evoking a Zollinger-Ellison syndrome. The secretin stimulation test and gastrin tumoural immunohistochemistry were, however, negative. We suggest that the concomitant tumoural production of gastrin-releasing peptide was responsible for the gastric hyperacidity and hypergastrinemia. This hormone probably also accounted for a moderate hypercorticism.
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PMID:Hyperprealbuminemia, euthyroid hyperthyroxinemia, Zollinger-Ellison-like syndrome and hypercorticism in a pancreatic endocrine tumour. 256 80

The regulation of gastrin gene transcription was studied in GH4 pituitary cells transfected with constructs comprised of the first exon of the human gastrin gene and various lengths of 5' regulatory sequences ligated upstream of the reporter gene chloramphenicol acetyltransferase. Gastrin reporter gene activity in GH4 cells was equal to the activity of a reporter gene transcribed from the endogenously expressed growth hormone promoter. The effect of a variety of peptides on gastrin gene transcription including epidermal growth factor (normally present in the gastric lumen), gastrin-releasing peptide, vasoactive intestinal peptide, and somatostatin (present in gastric nerves) was assessed. Epidermal growth factor increased the rate of gastrin transcription almost 3-fold, whereas thyrotropin-releasing hormone and vasoactive intestinal peptide increased gastrin transcription 2- and 1.5-fold, respectively. Gastrin-releasing peptide, a peptide that strongly stimulates gastrin release, weakly increased gastrin transcription (1.3-fold). Somatostatin inhibited the increase in gastrin transcription induced by epidermal growth factor, thyrotropin-releasing hormone, and vasoactive intestinal peptide. Constructs containing various lengths of 5' regulatory sequences defined a response element -40 to -82 base pairs (bp) 5' to the transcription initiation site. This 40-bp sequence contains Sp1 and AP2 binding sites, which suggests that epidermal growth factor and thyrotropin-releasing hormone stimulate gastrin gene transcription through transcription factors that bind to Sp1 and/or AP2 motifs.
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PMID:Regulation of the gastrin promoter by epidermal growth factor and neuropeptides. 256 64


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