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)

Heptadecapeptide gastrins (G17) have been purified and sequenced from a variety of species. However, progastrin (G34) sequences have been determined only for pig and human from purified peptides and for rat from cDNA. Since G34 in most species accounts for only approximately 5% of total antral gastrin, micropurification techniques must be employed to avoid the need for large quantities of antral tissue. Efficient purification methodology yielded 1.5 and 1.3 nmol of G34 from the antrum of a single goat and of a single dog, respectively. The N-terminal pyroglutamyl residues were enzymatically removed and the peptides were sequenced through to the proximity of their COOH-termini. The COOH-terminal sequences of goat and dog G34 were confirmed by sequencing the corresponding deblocked G17 from each animal. The previously published dog G17 sequence was shown to be incorrect. The sequences for dog and goat G34 are: Dog less than ELGLQGPPQLVADLSKKQGPWMEEEEAAYGWMDF# Goat less than ELGLQDPPHMVADLSKKQGPWVEEEEAAYGWMDF# Dog and goat gastrins differ in 3 sites in the 17 amino acid NH2-terminus and only a single site in G17 (the sites of differences are underlined). The ratio for sulfated to non-sulfated antral G17 is 9:1 for the goat and 1:9 for the dog.
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PMID:Sequences of gastrins purified from a single antrum of dog and of goat. 376 41

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.
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PMID:Immunocytochemical evidence for differential distribution of gastrin forms using region-specific monoclonal antibodies. 377 Mar 52

In an effort to identify and characterize precursors of gastrin in tissues, we generated region-specific antisera against a synthetic progastrin peptide, Try-Gly-Trp-Met-Asp-Phe-Gly-Arg-Arg (GL9), as deduced from the nucleotide sequence of gastrin mRNA. This antisera did not cross-react with gastrin or progastrin peptides with shorter carboxyl-terminal extensions. Progastrin-like immunoreactivity (PGLI) was measured in porcine antrum at a concentration of 6.8 +/- 1.2 pmol/g wet weight (mean +/- SE, n = 5), or roughly 0.2% of that of gastrin. On Sephadex G50 chromatography, a major peak of PGLI was eluted as a slightly larger molecule than gastrin heptadecapeptide (G17) but possessed the same N-terminal immunoreactivity. These findings suggest that G17 may be formed by processing of a carboxyl-terminally extended precursor as an alternative to cleavage of big gastrin (G34).
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PMID:Progastrin-like immunoreactivity in porcine antrum: identification and characterization with region-specific antisera. 383 47

We developed a radioimmunoassay specific for glycine-extended progastrin processing intermediates (G-Gly) using antisera generated against the synthetic peptide Tyr-Gly-Trp-Met-Asp-Phe-Gly. Distribution of immunoreactivity in the porcine gastrointestinal tract obtained with this antibody paralleled that of gastrin with the mucosa containing the highest quantity, 116 +/- 22 pmol/g, wet weight (mean +/- S.E., n = 5), or roughly 4% of gastrin concentration. This immunoreactivity was localized specifically to antral mucosal G-cells by immunohistochemistry. On Sephadex G-50 column chromatography of porcine antral mucosal extracts glycine-extended progastrin processing intermediates were separated into three principal molecular forms, each corresponding to known molecular forms of gastrin, component I, tetratriacontagastrin (G34) and heptadecagastrin (G17). Following purification by antibody-coupled affinity chromatography, one molecular form corresponding to G17 in size was shown to have an amino terminus identical to that of G17. Another molecular form corresponding to G34 in size could be converted to the molecular form corresponding to G17 by tryptic digestion. Our findings indicate that glycine-extended progastrin processing intermediates may serve as immediate precursors for each molecular form of gastrin, thus suggesting an alternative pathway for gastrin biosynthesis more complex than that previously conceived.
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PMID:Identification and characterization of glycine-extended post-translational processing intermediates of progastrin in porcine stomach. 384 Jan 61

Ontogenesis of gastrin cells was studied in the pyloroduodenal mucosa of the mouse using anti-human G17 serum, R-1301, and anti-human G34(1-15) serum, R-2703. R-1301-immunostained cells first appeared in the pyloric mucosa of 14-day-old fetuses. Cells stained with both R-1301 and R-2703 appeared immediately after birth, and gradually increased in number to the adult level. Most R-1301-reactive cells were also reactive to R-2703, whereas some cells that reacted with R-1301 exhibited very weak or no reaction with R-2703. The discrepancy between these two immunoreactivities is discussed. In the duodenum, a considerable number of R-1301-reactive cells were present from the perinatal stage and through out adult development. A few R-2703-reactive cells were seen in the duodenum of young mice but not of the adult.
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PMID:Ontogenesis of gastrin cells in the pyloric antrum and duodenum of the mouse. 388 46

Region-specific antisera to three enkephalins: met-enkephalin, met-enkephalin-Arg6-Phe7 and met-enkephalin-Arg6-Gly7-Leu8, together with four region specific antisera to progastrin: C-terminal G17 specific, N-terminal G34 specific, cryptic peptides A- and B-specific, were used in immunohistochemical studies of hog antral mucosa. A sub-population (6-10%) of the gastrin-containing endocrine cells (G-cells) was found to react with antisera to met-enkephalin, met-enkephalin-Arg6-Phe7 and met-enkephalin-Arg6-Gly7-Leu8. About 30% of all the enkephalin-containing cells were identified as G-cells. The results indicate that a fraction of G-cells produces both enkephalin-like peptides and gastrin.
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PMID:Occurrence of met-enkephalin, met-enkephalin-Arg6-Phe7 and met-enkephalin-Arg6-Gly7-Leu8 in gastrin cells of hog antral mucosa. 399 57

A radioimmunoassay has been developed using antibodies to a synthetic analogue of the C-terminal hexapeptide sequence of the porcine gastrin precursor. Boiling water extracts of porcine antral mucosa contained immunoreactive material that diluted in parallel with standard peptide. Concentrations of immunoreactivity were 5.5 +/- 0.8 nmol X g-1 (mean +/- S.E.M.) in antral mucosa and were closely similar to those of C-terminal heptadecapeptide gastrin immunoreactivity (5.0 +/- 0.6 nmol X g-1). Approximately 30-fold lower concentrations were found in porcine duodenum. A similar distribution was found in ferret, but human, rat and chicken antrum did not contain significant quantities of immunoreactivity. Gel filtration of porcine antral extracts on Sephadex G-50 revealed a single peak of immunoreactivity eluting in a similar position to G17, but on anion-exchange chromatography two peaks of immunoreactive material were separated. These also differed in their retention time on reverse phase HPLC. Both peptides are probably derived by tryptic cleavage at the C-terminus of porcine preprogastrin. No evidence was found to suggest that there are significant quantities of unprocessed preprogastrin in hog antral mucosa. The precise chemical difference between the two immunoreactive peptides identified here remains to be established; together, however, they provide specific markers for progastrin synthesis.
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PMID:Identification by specific radioimmunoassay of two novel peptides derived from the C-terminus of porcine preprogastrin. 403 6

Methods are described for obtaining antisera specific for the NH2-terminal regions of human and porcine big gastrin (G34) that can be used in radioimmunoassays. Three antisera have been characterized in detail: one (L66) raised to human 1--15 (Tyr7-Pro8-Ser9) G34 has an antigenic determinant in the 1--6 region of human G34; a second (L107) raised to 1--19 hG34 has an antigenic determinant in the 1--12 region. Both these antisera react weakly with porcine G34. A third antiserum (L33) raised to porcine G34 has an antigenic determinant in the 1--12 region of this peptide, and reacts weakly with human G34. In human antral extracts fractionated on Sephadex G50, L66 and L107 revealed a minor peak of immunoreactivity corresponding to G34, and a major peak corresponding to the NH2-terminal tryptic peptide of G34. Concentrations of the latter peptide were closely similar to those of G17 (i. e.) the COOH-terminal tryptic peptide of G34), consistent with the idea that G34 is cleaved within G-cells by a trypsin-like enzyme to yield G17. Antiserum L33 revealed small amounts of immunoreactivity in antral extracts of dog and cat, but did not reveal significant immunoreactivity in rat antral extracts. In contrast, L66 reacted with rat antral extracts, but not dog or cat. The sequences of G34 in these species are not known, but the results suggest significant differences compared with human and porcine G34, and indicate a high degree of species-specificity with NH2-terminal G34 antisera.
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PMID:Immunochemical studies on big gastrin using NH2-terminal specific antisera. 616 51

This work describes a new preparation of dog pancreatic acini which were used to study amylase release in response to various secretagogues. Neither secretin nor vasoactive intestinal peptide stimulated amylase release from acini. Caerulein, carbachol and human synthetic gastrin G17 stimulated amylase release with the same efficacy, but with different potencies. Bombesin nonapeptide did not show any evidence of a direct stimulatory effect on amylase release. These species-related peculiarities stress the necessity of using the same species when comparing pancreatic cell behaviour in vivo and in vitro.
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PMID:Action of secretagogues on amylase release from dog pancreatic acini. 616 10

The use of protein A- and IgG-conjugated colloidal gold staining methods for the immuno-localisation of peptide hormones and neurotransmitters at light- and electron microscope level are described and discussed. Bright-field and dark-ground illumination modes have been used to visualise the gold-labelled antigenic sites at the light microscope level. Immunogold staining procedures at the ultrastructural level using region-specific antisera have been adopted to localise specific molecular forms of peptides including gastrin (G17 and G34), glucagon and pro-glucagon, insulin and pro-insulin, in normal tissue and in tumours of the gastroenteropancreatic system. Similar methods have been used to demonstrate the heterogeneity of p-type nerves in the enteric nervous system. Vasoactive intestinal polypeptide (VIP) has been localised to granular sites (mean +/- S.D. granule diameter = 98 +/- 19 nm) in nerve terminals of the enteric plexuses and in tumour cells of diarrhoeogenic VIP-producing neoplasias (mean +/- S.D. granule diameter = 126 +/- 37 nm) using immunogold procedures applied to ultraviolet-cured ultrathin sections. Co-localisation of amines and peptides in carotid body type I cells and in chromaffin cells of normal adrenal medulla and phaeochromocytomas has also been demonstrated. Advantages of the immunogold procedures over alternative immunocytochemical techniques are discussed.
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PMID:Immunogold staining procedure for the localisation of regulatory peptides. 618 90


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