Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A soluble somatostatin-binding protein was detected in the cytosol fractions of various rat, human and bovine tissues. Maximum binding occurred at pH8.0-8.5 and was Ca(2+)-dependent. The specific binding of somatostatin per 10mug of cytosol protein from 12 rat tissues ranged between 36 and 15%, and 3% for peripheral blood cells. There was also substantial binding in cytosol from human anterior pituitary and liver, and bovine anterior pituitary. The specific binding in rat and human plasma in the presence of EDTA was only 1%. Gel filtration suggested a molecular weight of approx. 80000 for the somatostatin-binding protein from several sources. Exposure of the binding protein to trypsin eliminates somatostatin-binding activity but ribonuclease and deoxyribonuclease have no effect. The binding protein is thermolabile, ethanol-precipitable, and not completely specific for somatostatin. Bound (125)I-labelled [Tyr(1)]somatostatin is not easily displaced by excess of unlabelled somatostatin. The effects of dithiothreitol and mercaptoethanol on the binding of (125)I-labelled [Tyr(1)]somatostatin to the binding protein suggests that binding involves two sequential steps, first loose binding, then disulphide linkage. Since semipurified somatostatin-binding protein causes a dose-related inhibition of the binding of (125)I-labelled [Tyr(1)]somatostatin in radioimmunoassays for somatostatin, estimates of somatostatin content of tissue extracts by radioimmunoassay in some cases may be spuriously high. It is not yet clear whether the binding protein is a true cytosol protein or an easily solubilized membrane protein.
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PMID:Properties of soluble somatostatin-binding protein. 2 54

Functional gastrin-containing tumor cells (GT cells) have been maintained in short-term culture on microporous membranes, and their response to selected agents has been determined. After dispersion of gastrinoma by collagenase-DNAase digestion coupled with mechanical disruption, dispersed cells were depleted in stromal material by selective attachment to a plastic substrate, then cultured for 72 hours on porous cellulose membranes. Cultures contained 68 +/- 5% GT cells with a viability of 92 +/- 2%. Secretin stimulated the rate of gastrin release from cultured GT cells in both a time- and a dose-dependent fashion. To examine the possible involvement of adenylate cyclase- and protein kinase C-mediated mechanisms in regulating gastrin release from the neoplastic GT cells, we evaluated the effects of 8-bromoadenosine 3':5'-cyclic monophosphate (8-BrcAMP; 10(-4) - 10(-2) mol/L), the diterpene forskolin (10(-5) mol/L), 12-0-tetradencanoylphorobol 13-acetate (TPA; 10(-8) - 10(-6) mol/L), and 4 alpha-phorbol 12,13-didecanoate (4 alpha PDD; 10(-8) - 10(-6) mol/L) on gastrin release. Among all compounds tested, 8-BrcAMP (10(-2) mol/L) was the most potent, stimulating the rate of gastrin release 263% above basal. Both 8-BrcAMP and TPA stimulated gastrin release in a dose-dependent fashion. The biologically inactive phorbol ester, 4 alpha PDD, was without effect at all concentrations. Somatostatin (10(-8) - 10(-6) mol/L) inhibited 8-BrcAMP-stimulated gastrin release in a dose-dependent fashion to a maximum of 75%.
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PMID:Control of gastrin release in cultured gastrinoma-derived G cells. 289 16

To identify the nuclear protein(s) that interact with the putative cAMP response element (CRE) of the rat angiotensinogen (ANG) gene (i.e. nt 806-779 upstream of the transcriptional start site), mouse liver nuclear proteins were prepared for the present studies. The DNase 1 footprinting protection analysis revealed that nt -799/-788 in the 5'-flanking region of the rat ANG gene are protected by the mouse liver nuclear protein. Gel mobility-shift assays revealed that the addition of the unlabelled DNA fragment, ANG nt -806/-779 competed effectively with the binding of the labelled ANG nt -806/-779 to the mouse liver nuclear proteins but the addition of unlabelled mutants of ANG nt -806/-779 were only weakly effective in competing with the labelled ANG nt -806/-779. The addition of unlabelled CRE of the somatostatin (SOM) gene and the CRE of the tyrosine aminotransferase (TAT) gene was also ineffective in competing with the labelled ANG nt -806/-779. Southwestern blot analysis revealed that the labelled ANG nt -806/-779 interacted with two mouse liver nuclear proteins with apparent molecular masses of 52 and 43 kDa, whereas the labelled SOM-CRE, TAT-CRE and the CRE of the phosphoenolpyruvate carboxykinase (PEPCK) gene interacted with one molecular species of 43 kDa. The binding of the labelled ANG nt -806/-779 to the 52 kDa protein was effectively competed for by the addition of unlabelled ANG nt -806/-779 but not by unlabelled SOM-CRE, TAT-CRE and PEPCK-CRE. Finally, Western blot analysis revealed that polyclonal antibodies against the CRE-binding protein (CREB) interacted with the mouse liver nuclear 43 kDa protein but not with the 52 kDa protein. These studies demonstrate that the CRE of the rat ANG gene (ANG nt -806/-779) interacts with the 43 kDa CREB and a novel 52 kDa protein from mouse liver. The novel 52 kDa protein is immunologically distinct from the 43 kDa CREB. These studies suggest that the 52 kDa protein might have a role in the expression of the hepatic ANG gene.
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PMID:Identification of a novel mouse hepatic 52 kDa protein that interacts with the cAMP response element of the rat angiotensinogen gene. 944 91

Administration of somatostatin to rats induced a transient reduction of serum levels of deoxyribonuclease I (DNase I) activity in a dose-dependent manner, followed by a substantial decrease of DNase I activity in the lower gut. Activity in the parotid gland, liver, and kidney did not change. Real-time PCR analysis of the DNase I gene transcript in ileum indicated that the decrease was due to down-regulation of gene expression. Based on these responses, rat tissues expressing DNase I could be classified into two types, somatostatin-sensitive and somatostatin-resistant, and the level of DNase I activity in the lower gut seems to be controlled by somatostatin.
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PMID:Tissue-specific in vivo inhibition of DNase I gene expression by somatostatin. 1132 95