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)

Autoradiographic analysis of radioligand binding was used to localize and characterize cholecystokinin (CCK) receptors expressed in the stomach and gallbladder of the American alligator (Alligator mississippiensis). Alligator gallbladder smooth muscle expresses a CCK-A receptor subtype, and stomach oxyntic mucosa expresses a distinct receptor subtype, termed CCK-B/X because of its similarities to both CCK-B and CCK-X receptors. Both the gallbladder and the stomach binding sites have very low affinities for a panel of nonpeptide receptor agonists and antagonists that are selective for mammalian CCK-A and CCK-B receptors. These results suggest that CCK receptor subtypes diverged from the ancestral CCK-X receptor in an early amniote, prior to the divergence of mammals and reptiles in vertebrate phylogeny, and that CCK-A receptors may have evolved before CCK-B receptors. Our findings support the hypothesis that the evolution of gastrin preceded the evolution of two separate CCK receptor subtypes.
Gen Comp Endocrinol 1997 Jan
PMID:CCK-A- and CCK-B-like receptors in the gallbladder and stomach of the alligator (Alligator mississippiensis). 900 Apr 71

Gastrin-like immunoreactive peptides were extracted from the gastric antrum of the American alligator (Alligator mississippiensis) and purified by fractionation using C18 Sep-Paks, Sephadex G-50, pH stable C8 reversed-phase HPLC, and C18 reversed-phase HPLC. Three major immunoreactive peaks were purified and found to correspond to 49, 45, and 34 residue peptides by microsequence analysis. The amino acid sequence of the largest peptide was DWLASLSQDQ KHLISKFLPH IYGELAN QEN YWQEDDALHD HDYPGWMDF-amide. The two smaller peptides corresponded to carboxyl-terminal 45 and 34 residue fragments of the 49 residue peptide. The putative proteolysis of the 49 residue peptide to the two shorter peptides occurs at cleavage sites that are unusual in biosynthetic processing. Mass spectral analysis confirmed the molecular weights that were predicted from the amino acid sequences, thus revealing the absence of any post-translational modifications, such as sulfation. Although the three alligator gastrins resemble mammalian cholecystokinin in having a tyrosine residue in the seventh position from the carboxyl terminus, this tyrosine is apparently nonsulfated as in turtle gastrin. When tested by radioreceptor assay, a synthetic replicate of alligator gastrin-49 exhibited a gastrin-like pattern of biological activity on mammalian CCK-A and CCK-B receptors. Comparison of the amino acid sequences of known peptides revealed that alligator gastrin is most similar to turtle gastrin (76% identical), followed by frog gastrin (51% identical), chicken gastrin (49% identical), and human gastrin (12% identical). These similarities closely reflect vertebrate phylogeny and support the hypothesis that functionally distinct gastrins evolved from CCK in early tetrapods. However, gastrin evolved via different mechanisms in the mammalian lineage (mechanism unknown) versus the amphibian and reptilian/avian lineages, in which two different single nucleotide base changes can account for the separate evolution of amphibian gastrin and reptilian/avian gastrin.
Gen Comp Endocrinol 1997 Nov
PMID:Purification, amino acid sequence, synthesis, and receptor selectivity of alligator gastrin. 935 27

Expression of 25 mRNAs in a single human lymphocyte was investigated using the reverse transcription nested polymerase chain reaction (RT nested PCR) method. Proteins corresponding to the mRNA investigated were mucin antigen, melanoma antigen, pregnancy-specific beta-1 glycoprotein 4, phenylethanolamine-N-methyl-transferase, beta B3-crystallin, homeobox 4A, interleukin 2, cluster of differentiation 8, progesterone receptor, parathyroid hormone, gastrin, cholecystokinin/pancreozymin, glucagon, insulin, enkephalin, thyroid stimulating hormone, adrenocorticotropic hormone, synapsin I, immunoglobulin (Ig)M, IgD, IgG1, IgG3, IgE, IgA, and T cell receptor alpha. All mRNAs were detected in single lymphocytes of two individuals, without exception. In addition, transcripts of IgM, IgD, IgG1, IgG3, IgE, IgA, and the T cell receptor a gene were detected in single sperms. The results strongly suggest the possibility that all mRNAs may be expressed in a single human cell, of both somatic and germ lineage. Thus, cells can consume energy in vain to produce functionally meaningless gene transcripts. However, this basal or illegitimate transcription may be essential for the birth of living matter: the arrow of time in a cell. Moreover, the phenomenon implies the potential of using lymphocytes in place of inaccessible tissue for the diagnosis of genetic diseases.
Mol Gen Genet 1998 May
PMID:A single human cell expresses all messenger ribonucleic acids: the arrow of time in a cell. 964 29

Many regulatory peptides form families with at least two homologous members. For several such families the divergence of the individual members from a common ancestor can be dated to early in vertebrate history. Cholecystokinin (CCK) and gastrin were originally identified in mammals. Recently, two distinct members of the CCK/gastrin family were identified in the bullfrog (Rana catesbeiana), termed CCK and gastrin. Frog gastrin is very similar to CCK in the region defining biological activity. To evaluate whether the two endogenous peptides have distinct properties, their effects were studied in typical target organs. While porcine gallbladder responded equally to frog gastrin-8 and CCK-8, EC50 values for stimulation of bullfrog gallbladder contractions were 490 nM (gastrin) and 69 nM (CCK). In contrast, gastrin appeared to be a more potent stimulant of acid secretion than CCK; the estimated EC50 values are 3.1 and 17.2 nM, respectively. Furthermore, gastrin had a significantly higher efficacy than CCK-8s. Thus, in spite of their close structural resemblance, there are clear differences between the two endogenous peptides in their action on gallbladder and gastric mucosa. It is concluded that there are distinct gastrin and CCK functions already at the amphibian level of evolution.
Gen Comp Endocrinol 1998 Nov
PMID:Gastrin and cholecystokinin of the bullfrog, Rana catesbeiana, have distinct effects on gallbladder motility and gastric acid secretion in vitro. 978 8

1. The involvement of beta3 adrenoceptors in the control of gastric acid secretion and histamine release was investigated in the dog. 2. In conscious dogs, SR 58611A (0.0625-1.0 mg/kg/hr i.v.) dose dependently inhibited gastric acid secretion induced by pentagastrin. Maximal inhibition (40%) was obtained with the dose of 1 mg/kg. Ritodrine (1 mg/kg/hr i.v.) also induced a marked inhibition (85%) of gastric acid secretion stimulated by pentagastrin. 3. On 2-deoxy-D-glucose-stimulated acid secretion, both SR 58611A and ritodrine at 1 mg/kg/hr i.v. showed inhibitory effects. On these experiments, ritodrine, but not SR 58611A, significantly reduced plasma gastrin concentrations. 4. In anaesthetized dogs, histamine concentrations from gastrosplenic vein increased fivefold after the infusion of pentagastrin. SR 58611A (1 mg/kg/hr i.v.) did not significantly modify the stimulant effect of pentagastrin on histamine release. In contrast, ritodrine (1 mg/kg/hr i.v.) significantly inhibited histamine release induced by pentagastrin. 5. These data suggest that beta3 adrenoceptors may participate in the negative control of gastric acid secretion in the dog, probably through a histamine-independent mechanism.
Gen Pharmacol 1998 Oct
PMID:Effects of beta3-adrenoceptor agonist SR 58611A on gastric acid secretion and histamine release in the dog: comparison with ritodrine. 979 27

The ECL cell is the predominant endocrine cell type in the oxyntic mucosa, displaying typical ultrastructure with numerous cytoplasmic vesicles and electron-dense granules. ECL cells have many features in common with neurons and other peptide hormone-producing endocrine cells, including the ability to produce, store, and secrete chromogranin-A and chromogranin A-derived peptides. In addition, they produce and store histamine and respond with activation and growth to a gastrin challenge. ECL cells are stimulated to secrete histamine as well as other products by gastrin and PACAP and are inhibited by somatostatin, galanin, and prostaglandins. The cytoplasmic vesicles are thought to contain histamine and other secretory products. Mature secretory vesicles occur in the docking zone of the ECL cells, where they constitute the releasable pool of secretory products. Gastrin stimulation will induce exocytosis and degranulation. Histamine released from ECL cells plays a key role in the regulation of parietal cell activity (the gastrin-ECL cell-parietal cell axis). In response to long-term gastrin stimulation, vacuoles and lipofuscin bodies develop in the ECL cells, forming part of a crinophagic pathway by which the ECL cell strives to eliminate superfluous secretory products.
Gen Pharmacol 1999 Apr
PMID:Rat stomach ECL cells up-date of biology and physiology. 1032 81

To understand the developmental process of the endocrine system, which controls the pancreatic exocrine function in Japanese flounder, Paralichthys olivaceus, the expression patterns of cholecystokinin (CCK) and pancreatic polypeptide (PP) during the larval stage were analyzed by immunohistochemistry and in situ hybridization. Expression of CCK in the intestinal epithelia started at 2 days posthatching (dph), 1 day prior to the first feeding. Endocrine pancreatic cells containing insulin were present in the pancreas primodium at hatching, and these endocrine cells formed an islet at 3 dph and developed into the principle islet neighboring gallbladder at 20 dph. However, PP cells were not contained in the principle islet even after metamorphosis. PP cells were contained in the accessory islets differentiated around the proximal part of the pyloric appendages at 30 dph (early metamorphosis stage). Therefore, we infer that the stimulative regulation of pancreatic enzyme secretion by CCK starts to function at the first feeding, whereas the restrictive regulation by PP develops about 1 month later in flounder larvae. In addition, we observed that CCK immunoreactive cells appeared in the accessory islets at 30 dph, similar to PP cells, even though CCK mRNA expression could not be detected in cells from the islets. This indicates the possibility that a peptide that is cross-reacted with the CCK antibody, i.e., gastrin, is synthesized in the flounder islets.
Gen Comp Endocrinol 2000 Oct
PMID:Development of cholecystokinin and pancreatic polypeptide endocrine systems during the larval stage of Japanese flounder, Paralichthys olivaceus. 1104 6

The ontogeny of the neurohormonal peptides vasoactive intestinal polypeptide (VIP), neurotensin (NT), substance P (SP), calcitonin gene-related peptide (CGRP), gastrin/cholecystokinin (GAS/CCK), and somatostatin (SOM) as well as serotonin (SER) and nitric oxide synthase (NOS) was investigated in the gastrointestinal tract of the urodele Ambystoma mexicanum, the axolotl, using immunohistochemical techniques. The first regulatory substances to appear were SP, SOM, and SER that could be immunohistochemically detected up from stage 1. At early stage 2, VIP immunoreactivity was observed infrequently in enteric nerve fibers. With the onset of external feeding at late stage 2, SP-immunoreactive (IR) and SER-IR endocrine cells and VIP-IR nerve fibers were present throughout the gastrointestinal tract. Furthermore, in the small intestine NT-IR and GAS/CCK-IR endocrine cells appeared. At stage 3, SER immunoreactivity was observed not only in endocrine cells but also in nerve fibers. CGRP-IR and SP-IR nerve fibers were detectable at stage 4 and stage 5, respectively. From stage 5 on, a minority of the CGRP immunoreactivity occurred in SP-IR nerve fibers. NOS immunoreactivity did not appear before stage 6 when it was found infrequently in nerve fibers. Thus, several phases of development can be distinguished: (1) at the yolk sac stages only few regulatory substances are present. (2) At the onset of external feeding, all endocrine cell types investigated were readily detectable. Thus, the onset of external feeding seems to trigger the development of the gastrointestinal endocrine system. (3) The endocrine cells are first found in the proximal part of the gastrointestinal tract and later in higher numbers in the distal parts. (4) The dually distributed neurohormonal peptides and SER first appear in endocrine cells and later additionally in nerve fibers. Thus, the nerve fibers likely set up the fine regulation of gastrointestinal blood flow and motility.
Gen Comp Endocrinol 2001 Jan
PMID:Ontogeny of neurohormonal peptides, serotonin, and nitric oxide synthase in the gastrointestinal neuroendocrine system of the axolotl (Ambystoma mexicanum): an immunohistochemical analysis. 1116 72

The regional distribution and relative frequency of neurohormonal peptides-producing endocrine cells were demonstrated in the alimentary tract of wrinkled frog, Rana rugosa, using eight types of specific antisera raised against mammalian regulatory peptides. The alimentary tract of frog was divided into six portions from esophagus to rectum. Most of the cells in the epithelial lining portion, between epithelial cells, were generally spherical or spindle shaped having long cytoplasmic process that was reached to the lumen (open-typed cell) while cells showing round shape (close-typed cell) were also found in the gastric, esophageal or intestinal glands occasionally. All of eight immunoreactive (IR) cells against serotonin, somatostatin, bovine Sp-1/chromogranin (BCG), gastrin, cholecystokinin (CCK)-8, bombesin, glucagon, and human pancreatic polypeptide (HPP) were observed in this study. Serotonin-IR cells were demonstrated throughout whole alimentary tract including esophagus and showed most predominant frequency in antrum. Somatostatin-IR cells were also detected throughout whole alimentary tract including esophagus and showed most predominant in pylorus and antrum. BCG-IR cells were restricted to stomach regions with relatively low frequencies. CCK-8-IR cells were observed from antrum to ileum and showed highest frequency in antrum. Gastrin-IR cells were restricted to antrum with low frequency and bombesin-IR cells were demonstrated from esophagus to antrum with various frequencies. Glucagon-IR cells were located throughout whole alimentary tract except for rectum and showed most predominant frequency at antrum. HPP-IR cells were detected from antrum to ileum with highest frequency in antrum. In conclusion, the regional distribution and relative frequency of these IR cells correspond well to the previous report in anuran species but somewhat peculiar patterns are also detected.
Gen Comp Endocrinol 2003 Mar
PMID:An immunohistochemical study on the neuropeptide-producing endocrine cells in the alimentary tract of wrinkled frog, Rana rugosa (Ranidae). 1262 Feb 41

Several neurohormonal peptides of the gastrointestinal system of fish have been revealed by immunohistochemical methods. Among salmonids, the rainbow trout, Oncorhynchus mykiss (Walbaum) is the most studied species, whereas the informations about other species of the taxonomic group are lacking. The regional distribution and relative densities of cells belonging to the neuroendocrine system have been in this paper demonstrated in the gut of the brown trout, Salmo trutta Linnaeus. In the gastric mucosa, endocrine cells were detected, which were immunoreactive to bombesin-, gastrin-, and secretin-antisera. Endocrine cells containing gastrin-, bombesin-, cholecystokinin-8-, glucagon-, and leptin-like immunoreactivities were present in the pyloric caeca and intestine. The pancreatic endocrine islets contained glucagon-, and, possibly, secretin-like-immunoreactive endocrine cells, as well as a contingent of galanin-like-immunoreactive nerve fibres. The exocrine pancreatic parenchyma showed bombesin-like-immunoreactive nerve fibres. Within the tested regulatory peptides, bombesin and leptin were observed in both endocrine cells and nerve cell bodies and fibres. Leptin was in addition detected in epithelial cells of the gastric glands. In the brown trout we have never observed any immunoreactivity to the VIP antiserum (either in the stomach or in the intestine). Some special structural patterns (in particular those ones related to galanin- and leptin-immunohistochemical data) have thus been detected for the first time in the brown trout, and provide further data for a better knowledge of gut morpho-functional aspects in this economically important fish.
Gen Comp Endocrinol 2004 Sep 01
PMID:An immunohistochemical study on the neuroendocrine system in the alimentary canal of the brown trout, Salmo trutta, L., 1758. 1530 66


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