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)

1. The effects of acetylcholine, catecholamines and gastrin on the intracellular content of cyclic AMP and cyclic GMP in antral circular muscle have been determined. 2. Acetylcholine results in a significant but transient increase in intracellular cyclic GMP. 3. Isoproterenol and norepinephrine increase intracellular cyclic AMP. Based on half-maximal effective doses, isoproterenol is 2.7-times more effective than norepinephrine. The increase in intracellular cyclic AMP by both agents is inhibited by propranolol but not phentolamine, indicating that both agents act on the muscle cell by a beta-receptor-coupled mechanism. 4. Gastrin has no demonstrable effect on either cyclic AMP or cyclic GMP. This suggests that while gastrin and acetylcholine can produce a like myoelectric response in the muscle cell, the action of gastrin is mediated by a separate receptor, presumably on the muscle cell, and not by a release of acetylcholine.
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PMID:Cyclic nucleotides of canine antral smooth muscle. Effects of acetylcholine, catecholamines and gastrin. 626 Feb 21

The membrane potentials of the smooth muscle cells of the sphincter of Oddi, gall bladder or common bile duct of the guinea pig was --56, --40 or --54 mV, respectively. The length constant of the tissue of the sphincter of Oddi was 1.7 mm and this value was larger than that measured in hypertonic solution. The smooth muscle cells of the gall bladder and common bile duct were always spontaneously active, while this was not the case with cells from the sphincter of Oddi, nevertheless, electrical stimulation consistently produced spike generation. Acetylcholine depolarized the membrane and increased the spike frequency in muscle cells of the sphincter of Oddi, gall bladder and common bile duct. However, noradrenaline produced alpha-adrenergic inhibitory action in the sphincter of Oddi and common bile duct, and alpha-adrenergic excitatory action in the gall bladder. Isoprenaline, a beta-adrenergic agent, induced an inhibitory action in the above three regions. Prostaglandin E1 (PGE1) suppressed the membrane activity in the sphincter of Oddi, and this response was similar to that observed in the circular muscle of the intestine. In the gall bladder, PGE1 accelerated the membrane activity. Gastrin and secretin did not affect the smooth muscle activity of the gall bladder but these agents slightly suppressed electrical and mechanical activities in the sphincter of Oddi. On the other hand, cholecystokinin markedly accelerated the electrical and mechanical activities in the gall bladder but these actions were weak in the sphincter of Oddi. Muscle properties of the smooth muscle cells of the biliary system are discussed in relation to the mechanism of bile expulsion through the sphincter of Oddi.
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PMID:Electrical and mechanical properties of smooth muscle cells of the guinea pig biliary system. 746 56

The histamine secreting enterochromaffin-like (ECL) cell is now recognized as the principal regulator of gastric acid secretion. Histamine is not only a primary modulator of acid secretion, but may be of relevance in gastritis and as a mitogen in gastric neoplasia. Study of the ECL cell has been limited since no pure preparation was available. We therefore developed a pure isolated ECL cell preparation with a purity of 90-95% as determined by total histamine content and chromogranin immunofluorescence. Trypan blue exclusion demonstrated > 95% viability. While gastrin and acetylcholine are known modulators of acid secretion, the role of adrenergic neurotransmitters has not been clearly delineated. The purpose of this study was to examine adrenergic modulation of ECL cell histamine release. To further define the inhibitory mechanisms of histamine secretion, we evaluated the mast cell histamine inhibitor sodium cromoglycate. Histamine secretion was determined by radioimmunoassay. Basal secretion was 0.6 +/- 0.2 nmol/10(3) cells. Gastrin stimulated histamine secretion with an EC50 of 3 x 10(-10) M. Octopamine (alpha-adrenergic agonist) (10(-11)-10(-4) M) failed to stimulate histamine secretion. Isoproterenol (beta-adrenergic agonist) stimulated histamine secretion (EC50, 6 x 10(-8) M) and was inhibited by propranolol (IC50 5 x 10(-10) M).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Adrenergic and cromolyn sodium modulation of ECL cell histamine secretion. 753 Mar 10

A 21 cm retroperitoneal cystic mass was excised from a 71 year old woman. The cyst was filled with a hemorrhagic fluid and contained a 5 cm parietal hemorrhagic nodule. On histology, the nodule was composed of a uniform population of round cells arranged in trabeculae and nests. The neoplastic cells were immunoreactive to cytokeratin, EMA, NSE, chromogranin A, pancreatic polypeptide (PP) and Gastrin (G). Ultrastructural observation of neurosecretory granules confirmed the neuroendocrine nature of the tumor. No other lesions were detected and a diagnosis of primary epithelial neuroendocrine tumor was rendered. The histogenesis of the tumor including the possibility of a paraganglionic origin is discussed.
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PMID:Retroperitoneal cystic neuroendocrine tumor. A case report. 886 85

Although the enterochromaffin (EC) cell is one of the primary neuroendocrine regulatory cells of the small intestine, the lack of a purified cell system has precluded characterization of the cell and limited precise physiological evaluation. We developed methodology to obtain a pure population of Mastomys ileal EC cells, evaluated their functional regulation, and defined the transcriptome. Mastomys ilea were everted, end ligated, pronase-collagenase digested, and Nycodenz gradient centrifuged, and EC cells were collected by fluorescence-activated cell sorting (FACS) of acridine orange-labeled cells. Enrichment was confirmed by immunostaining of tryptophan hydroxylase and chromogranin A, specific EC cell markers, serotonin content, EC cell marker gene expression, and electron microscopy. Pituitary adenylate cyclase-activating polypeptide (PACAP), somatostatin, and gastrin receptor expression was determined by real-time RT-PCR. Live post-FACS-sorted cells were cultured, and the effects of forskolin, isoproterenol, acetylcholine, GABAA, PACAP-38, and gastrin on serotonin secretion were measured by ELISA. GeneChip Affymetrix profiling of FACS-sorted cells was undertaken to obtain the EC cell transcriptome. FACS produced a >70-fold enrichment of EC cells with a serotonin content of 240 +/- 22 ng/mg protein. Preparations were 99 +/- 0.7% pure by immunostaining for tryptophan hydroxylase. Vasoactive intestinal peptide/PACAP receptor 1 (VPAC1) and somatostatin receptor 2 were present, whereas PACAP receptor 1 (PAC1) and CCK2 receptors were undetectable. Forskolin, isoproterenol, and PACAP-38 stimulated serotonin secretion at EC50 values of 5 x 10(-10), 4.5 x 10(-10), and 1.2 x 10(-9) M, respectively. Isoproterenol stimulated cAMP levels by approximately 3.5 +/- 0.62-fold vs. unstimulated cells (EC50 of approximately 10(-9) M). Octreotide, acetylcholine, and GABAA inhibited serotonin secretion with IC50 values of 3 x 10(-11), 3 x 10(-10), and 2.9 x 10(-10) M, respectively. Gastrin had no effect on serotonin secretion. The naive EC cell transcriptome revealed highly expressed EC cell marker genes, the absence of marker genes for other small intestinal cell types, and a receptor profile that included cholinergic, adrenergic, dopaminergic, serotoninergic, GABAergic, and prostaglandin receptors. We were able to isolate homogeneous preparations (>99%) of live ileal EC cells and demonstrated regulation of serotonin secretion as well as established the normal EC cell transcriptome. Application of this methodology to normal and diseased human ileum will facilitate the elucidation of the pathophysiology of EC cells.
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PMID:Isolation, functional characterization, and transcriptome of Mastomys ileal enterochromaffin cells. 1645 86


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