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)

Antisera specific for the C-terminus of Met-enkephalin and two of its variants isolated from adrenal medulla and brain, namely Met-enk Arg6 and Met-enk Arg6Phe7, have been used in immunohistochemical studies of the gastrointestinal tract in rat, mouse and guinea pig. Met-enk and Met-enk Arg6Phe7-like immunoreactivities were found with similar distribution in nerve cell bodies of the myenteric plexus, and in fibers that were particularly dense in the myenteric plexus and circular smooth muscle. The Met-enk Arg6 antiserum showed weak staining of nerve cells and fibers. In rat and mouse, the antiserum to Met-enk Arg6Phe7, but not those to Met-enk or Met-enk Arg6, also stained numerous endocrine-like cells of the antral mucosa. These were identified as gastrin cells by elution and re-staining experiments with C-terminal gastrin antisera. The rat and mouse gastrin cells might conceivably express the enkephalin gene, but fail to process it to yield Met-enkephalin; alternatively, the Met-enk Arg6Phe7-like immunoreactivity in gastrin cells could be due to a cross-reacting peptide that does not belong to the opioid series.
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PMID:Immunohistochemical studies on the gastrointestinal tract using antisera to Met-enkephalin and Met-enkephalin Arg6Phe7. 635 86

Various tumor cells contain chromatographically distinct isoacceptor tRNA species. To decide whether the tumor-specific species represent an expression of a separate tRNA gene or only an undermodified form of normal tRNAPhe, nucleotide sequences of tRNAPhe isolated from neuroblastoma and normal mouse liver were determined by postlabeling techniques. The results showed identical sequences except for the changes of post-transcriptional modifications in the anticodon loop. Normal mouse liver tRNAPhe contained Cm32, Gm34, and the hypermodified YOH next to the 3' end of the anticodon. On the contrary, tRNAPhe from neuroblastoma contained C32, G34, and, instead of YOH base m1G. A small proportion of tRNAPhe species contained an undermodified YOH base. For the examination of the conditions leading to the undermodified tRNAPhe, Vero cells derived from the kidney of African green monkey in culture were used. In these cells, deprivation of methionine or lysine resulted in changes in tRNAPhe modification similar to those in tumor cells. Ehrlich ascites tumor cells were examined to determine whether the presence of altered tRNAPhe species in various tumors is also the result of starvation of some nutritional factors. Results obtained with these cells showed that tRNAPhe species lacking the Y base disappeared in tumor-bearing mice after intraperitoneal injection with a mixture of amino acids and vitamins. Thus it is concluded that tumor-specific tRNAPhe species are the products of aberrant post-transcriptional modification, not the transcripts of different, normally repressed genes.
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PMID:Alterations in post-transcriptional modification of the Y base in phenylalanine tRNA from tumor cells. 640 57

In the central nervous system of the pond snail Lymnaea stagnalis a large number of elements (cells and fibers) can be identified with antisera (a-FM) to the molluscan cardioactive tetrapeptide FMRFamide (Phe-Met-Arg-Phe-NH2). Of these elements some are also reactive to antivasotocin (a-VT) and/or anti-gastrin (a-Gas). These observations suggest that the a-FM positive elements belong to more than one type. Previous results had already indicated that the immunoreactivity of many a-FM positive cells is influenced by the type of fixation. Taking into account the effects of three fixatives on the reactivity of the cells, and their staining characteristics with the two other antisera used, 8 a-FM positive types could be distinguished. Homologous and heterologous adsorptions were carried out to test the specificity of a-FM, a-VT and a-Gas. After homologous adsorptions no staining was obtained. After heterologous adsorptions only part of the multiple staining cells were identified. This indicates that in a-FM, a-VT and a-Gas in addition to (more) selective IgG molecules, less specific IgG molecules occur that can bind to other peptides than those used to raise the antisera (cross-reaction). The (more) selective IgG molecules in a-FM bind to 6 of the a-FM positive types, suggesting that in L. stagnalis a family of FMRFamide-like substances occurs. This conclusion is sustained by results obtained with a-FM adsorbed with fragments of FMRFamide.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Characterisation of multiple immunoreactive neurons in the central nervous system of the pond snail Lymnaea stagnalis with different fixatives and antisera adsorbed with the homologous and the heterologous antigens. 651 91

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

An oligo(dT)-primed cDNA copy of the mRNA coding for the human gastrin precursor was constructed from poly(A)-containing RNA from a human pancreatic, gastrin-producing tumor (a gastrinoma). The cDNA was inserted into the Pst I endonuclease site of plasmid pBR322 by the use of the poly(dC) and poly(dG) tailing procedure. Clones containing gastrin sequences were selected by hybridization to a purified single-stranded 32P-labeled gastrin cDNA probe. This probe was constructed with gastrinoma mRNA as template. As primer for the cDNA synthesis, we used a synthetic oligonucleotide mixture, d(AG-A-A-AG-T-C-C-A-T-C-C-A), corresponding to the gastrin-specific amino acid sequence Trp-Met-Asp-Phe. In this way we determined the nucleotide sequence of the entire coding region (303 nucleotides), the entire 3' untranslated region (102 nucleotides), and 8 nucleotides of the 5' untranslated region. A striking homology between parts of the coding region suggests that evolution of the gastrin gene has involved a gene duplication.
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PMID:Molecular cloning of human gastrin cDNA: evidence for evolution of gastrin by gene duplication. 657 56

A newly synthesized human big gastrin (G34) that was prepared according to the revised structure and that contained less than 3% oxidized methionine residues was compared with synthetic human little gastrin (G17) for acid-stimulating activity and clearance in human subjects. Prolonged infusions of each type of gastrin revealed that the time required to approach stable plasma concentrations was much longer for G34 than for G17. The time course of plasma gastrin concentration could be described by one-compartment models with half-lives of 44 min for G34 and 8 min for G17. After rapid intravenous infusion, G34 produced a much larger total acid response than did an equimolar dose of G17, and the responses were directly proportional to the integrated plasma gastrin increments. During the third hour of prolonged intravenous infusions of G34 and G17, the exogenous dosage of G34 required to produce the same blood concentration of gastrin was only one-fourth that of G17. Equivalent blood concentrations of G34 and G17 were associated with similar rates of acid secretion. These results suggest that G34 is more potent than has been thought, that it has an activity similar to that of G17 and that it must not be ignored in estimating total acid-stimulating activity of circulating gastrins. The measurement of total carboxyl-terminal immunoreactive gastrin can produce a good estimate of total acid-stimulating activity.
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PMID:Similar acid stimulatory potencies of synthetic human big and little gastrins in man. 671 38

Human little gastrin-I is known to exhibit a high tendency to air-oxidation of its methionine-15 residue to the corresponding S-oxide derivative, with concomitant loss of biological activity. Since its leucine-15 analog, even if fully biologically active, differs significantly from the parent hormone in the immunological properties, the norleucine-15 and methoxinine-15 analogues were synthetized. For the required comparative analyses new syntheses of human little gastrin-I and of its leucine-15 analog were additionally elaborated. Upon an optimized condensation of the fragments, followed by the deprotection step, partition chromatography as well as preparative high-performance liquid chromatography led to the desired gastrins in satisfactory yields and high degree of purity as judged by the expected and known side products.
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PMID:[Syntheses of human little gastrin-I and its leucine-15, norleucine-15 and methoxinine-15 analogs]. 684 Jul 3

With the aid of an indirect immunofluorescence technique neurons containing a gastrin-like substance were identified in the brain of Salmo gairdneri. The perikarya of these neurones appear to be located along the periventricular part of the nucleus lateralis tuberis between the hypophysial stalk and the most rostral tip of the saccus vasculosus. The fibres of these perikarya run rostrally toward the hypophysis, where they can be followed in the protrusions of the neurohypophysis into the proximal pars distalis. Here the bundle of immunoreactive fibres divides into numerous smaller bundles and into single fibres. Immunohistochemical specificity test have shown this immunoreactive substance to belong to the gastrin group, sharing an antigenic determinant with cholecystokinin (CCK) and pentagastrin (common amino-acid sequence Trp-Met-Asp-Phe). A possible function of these gastrin (or CCK)-containing neurones in the rainbow trout is discussed.
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PMID:Localization by immunofluorescence of a gastrin-like substance in the brain of the rainbow trout, Salmo gairdneri. 700 47

Peptides homologous to the gastro-intestinal hormones, gastrin and cholecystokinin (CCK), are present in the brain. Using immunohistochemistry we localized a neurosecretory system, reacting with antigastrin sera, in the brain of amphibians by light and electron microscopy. It has a dual location: (1) in the nucleus infundibularis ventralis (NIV) two groups of perikarya give rise to fibre tracts which join up in the infundibular floor and end in the external zone of the median eminence; (2) in the preoptic area nerve fibres and endings are found near the preoptic recess. At the electron microscope level, the immuno-colloidal-gold method revealed cells characterized by small immunoreactive dense granules, localized in the perikarya, nerve fibres and endings. Specificity controls showed that the immunoreacting substance(s) contain(s) all or part of the sequence (Trp-Met-Asp-Phe) common to gastrin, CCK and pentagastrin. The exact nature(s) and physiological function(s) of these substance(s) has (have) still to be defined.
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PMID:Gastrin-like peptides in the amphibian brain: an immunohistochemical study. 704 34


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