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

The metabolism of synthetic human heptadecapeptide gastrin (G17) in vivo, and in serum in vitro, was studied by radioimmunoassay using region specific antisera, gel filtration, ion exchange chromatography, and high performance liquid chromatography. After infusion of G17 intravenously in normal human volunteers, COOH-terminal and NH2-terminal immunoreactive G17 fragments were generated. At a steady state, approximately 15% of COOH-terminal immunoreactivity was attributable to G14-like material and up to 25% of total NH2-terminal immunoreactivity was attributable to two NH2-terminal fragments; one had the chromatographic properties of 1-13 G17, and the other was less acidic and less hydrophobic. After stopping the infusion of G17, the latter fragments accounted for progressively greater proportions of total gastrin activity. When G17 was incubated in serum in vitro, there was time-dependent and temperature-dependent loss of immunoreactivity, and again COOH-terminal and NH2-terminal immunoreactive fragments were formed. Removal of the NH2-terminal pyroglutamic acid was probably the rate limiting step because synthetic 2-17 G17 was degraded more rapidly in serum (t1/2, 2-3 h) than G17 (t1/2, 3-5 h). EDTA blocked degradation at the COOH-terminus of both 2-17 G17 and G17 but cleavage at the NH2-terminus still occurred, giving rise to a G14-like peptide. The rate of conversion of G17 in serum was not enough to account for the production of fragments in vivo, and it is proposed that these are formed when G17 encounters enzymes on cell surfaces, perhaps during passage through the capillary circulation. The production of these fragments needs to be considered in interpreting studies of the identity, metabolism, and release of gastrin in health and disease.
 ...
PMID:Metabolism of heptadecapeptide gastrin in humans studied by region-specific antisera. 240 13

Immunocytochemical identification of cellular origins of different forms of gastrin in canine and human antral mucosa has been carried out using region specific monoclonal antibodies. Three types of gastrin cells were identified. The first type of cell was stained with both the C-terminal specific antibody of G17 and the N-terminal specific antibody of G17. The second type of cell was stained only with the C-terminal specific antibody of G17 but not with the N-terminal specific antibody of G17. The third type of cell was stained only with the N-terminal specific antibody of G17. From these findings we propose that the first type of cell contains gastrins with the amidated C-terminus of G17 such as component 1, G34, G17, or G14 as well as the free N-terminus of G17 such as G17, or C-terminal extended gastrins, the second type of cell contains gastrins only with the C-terminus of G17 but not with the N-terminus of G17 such as G34, or component 1, and the third type of cell contains C-terminal extended gastrins with intact N-terminus G17.
 ...
PMID:Immunocytochemical evidence for differential distribution of gastrin forms using region-specific monoclonal antibodies. 377 Mar 52

1. In adult sheep and in lambs, over 95% of gastrin in the abomasal antrum was G17 with small amounts of G34 and lesser amounts of Component I. 2. Low gastrin concentration in the proximal duodenum was associated with a reduced percentage of G17. 3. The proportion of G34 increased progressively down the duodenum from a mean of 7% proximally to 47% in the most distal segment, and correlated negatively in any segment with the gastrin content. 4. In both the antrum and proximal duodenum, 60-70% of the G17 was in the sulphated form. 5. The gastroepiploic venous serum contained less G17 and more G34 than the tissues and up to 19% G14.
 ...
PMID:Low tissue gastrin content in the ovine distal duodenum is associated with increased percentage of G34. 809 47

Gastric cancer is a major cause of mortality and morbidity around world. However the effectiveness of the current approaches to the diagnosis and treatment of gastric cancer is limited. Recombinant targeted toxins may represent a novel direction of cancer therapy. In this study, we aimed to explore whether recombinant toxins fused with the truncated forms of G17 could target to kill cancer cells by recognizing CCK2R. Four recombinant Pseudomonas toxins PE38 fused with the forward or reverse truncated forms of G17 (G14 and G13) were successfully constructed, expressed, and purified. Their characteristics were further analyzed by SDS-PAGE, western blot and indirect immunofluorescence assay. The cytotoxicity assay demonstrated that only reversely fused recombinant toxins rG14PE38 and rG13PE38 exhibited certain toxicity on several cancer cell lines, and a competition assay indicated that the binding of the reverse gastrin-endotoxin to CCK2R (+) cells may be mediated by interaction between gastrin/gastrin-like and CCK2R.
...
PMID:Expression, purification and characterization of recombinant toxins consisting of truncated gastrin 17 and pseudomonas exotoxin. 2535 54