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 fetal rat intestinal cell (FRIC) culture model was established to investigate the factors controlling synthesis and secretion of somatostatin-28 (S-28) by the intestine. Immunohistochemical analysis demonstrated the presence of cells containing somatostatin-like immunoreactivity (SLI), many of which emitted long processes toward neighboring cells. Gel chromatography of SLI stored and secreted by nonstimulated FRIC cultures demonstrated a predominance of S-28 (59%), lesser amounts of S-14 (31%), and a minor peak of large molecular weight SLI (10%). Secretion of SLI was stimulated by treatment of cells for 2 h with 5 mM dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP; P less than 0.01) or 2 microM phorbol ester (P less than 0.05), but was unaffected by the calcium ionophore A23187 (2 micrograms/ml). Concomitant treatment with all three agents increased SLI secretion in an additive fashion to 254 +/- 25% of controls (P less than 0.0001). DBcAMP treatment did not alter the distribution of stored or secreted S-28 (59%) and S-14 (33%). After 24 h of exposure to DBcAMP, but not after treatment with phorbol ester, a threefold increment in prosomatostatin mRNA transcript levels was observed. FRIC cultures therefore synthesize and secrete a predominance of S-28 in a regulated manner, making them a promising model for future studies on the biosynthesis and secretion of intestinal somatostatin.
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PMID:Synthesis and secretion of somatostatin-28 and -14 by fetal rat intestinal cells in culture. 169 3

The mechanism of regulatory expression of human cytochrome P-450scc gene by cAMP was investigated in a transient expression system using Y-1 cells (mouse adrenal tumor cell line) and a chimeric DNA composed of the structural gene for bacterial chloramphenicol acetyltransferase and the 5' flanking upstream sequence of the cytochrome P-450scc (cholesterol desmolase) gene which was revealed to contain a DNA element(s) responsive to cAMP [Inoue, H. et al. (1988) Eur. J. Biochem. 171, 435-440]. Introduction of deletions and point mutations in the upstream regulatory sequence demonstrated that three regions were mainly required for response to cAMP. These regions contained a short similar sequence. All of them have a 5-bp motif GTCAT (or ATGAC) in common, and have at least two motifs which conserve four out of five base pairs of the consensus sequence of the cAMP-responsive element (CRE), CGTCA (or TGACG). They are all apparently necessary for regulation by cAMP. Gel mobility shift assays suggested that a binding factor(s) to these regions was present in the nuclear extracts of Y-1 cells and adrenal cortex tissues and appeared to be different from the somatostatin CRE-binding protein. Deletion analysis also suggested that the region around -44 was essential to the basal transcriptional activity. This region shows some similarity to the CTF NF-1 binding site [Johnson and McKnight (1989) Annu. Rev. Biochem. 58, 799-839].
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PMID:Structures of regulatory regions in the human cytochrome P-450scc (desmolase) gene. 184 89

This study was undertaken to determine the origin and forms of immunoreactive somatostatin (SLI) present in the pancreatic juice of cannulated nonanesthetized rats. The systemic origin of somatostatin (SS) was assessed from bolus intravenous injections of either I125-Tyr1-SS-14 or synthetic SS-14 under basal and stimulated pancreatic juice secretion, and from measurements of radioactivity and SS-14 in the collected juice. Gel filtration of pooled juice samples indicated that there were no forms of SS corresponding to standards of I125-Tyr1-SS-14 or SS-14, but radioactive material eluted in the area of either I125-Tyr or free iodine. Investigation of the presence of SS-14 in the juice by radioimmunoassay (RIA) led to the identification of a 23-kDa SS-like immunoreactive protein that did not correspond to any of the three known forms of SS present in the pancreatic tissue (Pro-SS, SS-28, and SS-14). By boiling the juice before the RIA, this 23-kDa protein was no longer detectable by RIA. These data suggest that this protein may be a "putative" enzyme, degrading the SS tracer in the RIA. This possibility is supported by the observation that boiled juice lost this capacity of interfering with the RIA. In conclusion, SS in the pancreatic juice, if present, is not from systemic origin and the juice contains an active thermosensitive substance degrading the SS tracer in the RIA.
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PMID:Origin and characterization of immunoreactive somatostatin in rat pure pancreatic juice. 196 58

CRH, GH-releasing hormone (GHRH), somatostatin (SRIH), and peptide histidine methionine (PHM) were measured by RIA in extracts of normal adrenal glands and in extracts from adrenal and extraadrenal pheochromocytomas. In normal adrenal glands, immunoreactive (IR) CRH, IR-SRIH, and IR-PHM were detectable, while IR-GHRH was undetectable. In all 11 cases of adrenal pheochromocytomas, the tumors contained 2 or more of these four IR-peptides. In particular, IR-CRH was found in 73% (n = 8) of adrenal pheochromocytomas, IR-GHRH in 91% (n = 10), IR-SRIH in 91% (n = 10), and IR-PHM in 82% (n = 9) of adrenal pheochromocytomas. There was no significant correlation among the concentration of these peptides in each tumor, i.e. the concentrations of the IR-peptides were independent of each other. In contrast to the adrenal pheochromocytomas, none of these 4 IR-peptides was detectable in 5 extraadrenal pheochromocytomas. Gel filtration of pooled extracts from adrenal pheochromocytomas showed that the major component of the IR-CRH, IR-GHRH, IR-SRIH, and IR-PHM eluted in the position of their synthetic counterparts. Our results suggest that 1) the normal adrenal gland contains IR-CRH, IR-SRIH, and IR-PHM, but not IR-GHRH; 2) all of the adrenal pheochromocytomas we examined contained a number of hypothalamic releasing or inhibiting hormones; 3) their tissue concentrations were independent of each other; and 4) all of the extraadrenal pheochromocytomas we examined contained no such IR-peptides. The presence of hypothalamic hormones in adrenal pheochromocytomas and their absence in extraadrenal pheochromocytomas may be due to the differences in the chromaffin cells of their origin. Our data may be helpful in the differential diagnosis between adrenal and extraadrenal pheochromocytomas.
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PMID:Immunoreactive corticotropin-releasing hormone, growth hormone-releasing hormone, somatostatin, and peptide histidine methionine are present in adrenal pheochromocytomas, but not in extra-adrenal pheochromocytoma. 196 22

In the present work, somatostatin-like immunoreactivity (SLI) in human milk was characterized. In the early postpartum period, SLI levels were highest on the first day after delivery, and then gradually declined. From the fifth day postpartum, SLI levels in milk seemed unchanged. On the fifth day after delivery, milk SLI was significantly (p less than 0.01) higher than plasma SLI (126.3 +/- 11.7 vs. 17.6 +/- 1.1 pmol/L). The results indicate an active transport from blood or synthesis of somatostatin within the mammary gland. Gel filtration studies of skimmed milk, as well as milk exposed to urea and HCl, and aspirated milk from the human premature newborn, revealed that the main portion of milk SLI either represents somatostatin covalently bound to a larger protein, or more likely, a high molecular weight variant of somatostatin.
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PMID:A characterization of immunoreactive somatostatin in human milk. 196 41

Previous data from our laboratory showed that prolonged exposure of cultural cerebral cortical cells to high potassium concentrations and veratridine resulted in the stimulation of immunoreactive somatostatin (IR-SRIF) synthesis and caused a major increase in its high molecular weight forms. Somatostatin (SRIF) synthesis by cortical and hypothalamic cells was also affected by thyroid hormone (TH). In the present work we have examined to what extent TH might also affect SRIF processing. Cerebral cortical cells maintained as monolayer culture for 7-10 days received triiodothyronine (T3) in concentrations of 10(-11) M and 10(-7) M for 48 h. We found that the total amount of IR-SRIF was increased by high T3 concentrations as reported previously. When the IR-SRIF was characterized by high pressure liquid chromatography (HPLC) or gel filtration, it was evident that thyroid hormone treatment modified the elution profile of IR-SRIF in cells and medium on Bio-Gel P-10 and HPLC, increasing somatostatin 28 (S-28) and decreasing somatostatin 14 (S-14). The results indicate that thyroid hormones affect SRIF processing, leading to a major increase in the synthesis of its high molecular weight forms.
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PMID:Influence of thyroid hormones on somatostatin processing in cultured cerebro-cortical cells. 197 Jan 33

We have screened the sequence of the 394 base pairs upstream of the main transcriptional start site of the promoter of the human parathyroid hormone (PTH) gene for well-known protein recognition motifs with the aim to identify potential positive or negative regulatory elements. Within this region we found a potential cAMP-response element (CRE) besides several other putative binding sites for transcription factors. We fused promoter regions that contain this element and extend beyond the transcription start site to an appropriate reporter gene (CAT) and transfected different cell lines with these constructs. Transient expression of the CAT gene from these hybrid genes could be shown to be significantly stimulated by forskolin or isoproterenol thus proving the responsiveness of the whole promoter region towards elevated cAMP levels. DNase I protection studies revealed protein binding around the putative CRE (PTH-CRE) and an adjacent CCAAT element. Gel retardation assays with the PTH-CRE as well as the well-characterized CRE from the rat somatostatin promoter indicated specific binding of the same protein to both elements, although with a slightly reduced affinity of the PTH-CRE. Both of these elements were also able to confer cAMP-responsiveness to a heterologous promoter.
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PMID:The promoter of the human parathyroid hormone gene contains a functional cyclic AMP-response element. 197 34

Specific antisera, raised in rabbits, against somatostatin 1-14, somatostatin 1-28, the fragment 1-12 of somatostatin 1-28, and prosomatostatin 20-36 were used for immunohistochemistry and gel filtration of the rat retina. With all antisera, immunoreactive perikarya could be located in the inner nuclear and ganglion cell layers. In the inner nuclear layer, amacrine cells with processes extending predominantly into the first sublayer of the inner plexiform layer were observed. Some processes extended also to the ganglion cell layer. In addition, somatostatin-immunoreactive interplexiform cells were present in the inner nuclear layer. In the ganglion cell layer, perikarya were found located in the midperiphery and in the far periphery of the retina. The neurons located in the midperiphery of the retina possessed a round perikaryon from which processes could be followed going into the inner plexiform layer, where they dichotomized in the third and first sublayers. The perikarya in the far periphery of the retina near the ora serrata exhibited an ovoid-shaped cell body from which processes extended horizontally in a bipolar manner in the layer itself. By use of an [35S]-labeled antisense oligonucleotide probe, in situ hybridization of the rat retina showed the presence of perikarya in the inner nuclear layer and ganglion cell layer containing mRNA encoding for prosomatostatin. Gel filtration of the retinal extracts followed by radioimmunoassay showed the presence of somatostatin 1-14, the fragment 1-12 of somatostatin 1-28, and prosomatostatin 1-64. However, somatostatin 1-28 was not detected. The results obtained in this study verify the presence of somatostatin 1-14 in the rat retina located in perikarya and processes in the inner nuclear and ganglion cell layers. The positive in-situ hybridization signals show that the intraneuronal somatostatin immunoreactivity is due to synthesis of the peptide and not uptake in the neurons. The presence of the somatostatin propeptide and fragments of this propeptide, in both intraretinal perikarya and fibers, indicate a posttranslational modification of this neuropeptide in the perikarya and the processes as well.
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PMID:Somatostatin and prosomatostatin in the retina of the rat: an immunohistochemical, in-situ hybridization, and chromatographic study. 198 Nov 46

A sensitive radioimmunoassay was developed for human epidermal growth factor (hEGF) in saliva and gastric juice. This method was sufficiently sensitive for an accurate measurement of hEGF in these biological fluids. The minimal detectable concentration of EGF was 30 ng/L. The imprecision profile of EGF standard curve had a CV less than 10% in the range of 0.1-3.0 micrograms/L. Serial dilution curves of saliva and gastric juice paralleled that of standard EGF. The antibody to hEGF showed no cross-reactivity with a large excess of growth factors, such as human transforming growth factor alpha, human insulin-like growth factor I, and platelet-derived growth factor (c-sis). No detectable cross-reactivity was observed with some biological gut peptides: somatostatin, gastrin, secretin or pancreatic polypeptide. The intra-assay CV for saliva and gastric juice was less than 10%, and the recoveries were 93.9 +/- 8.7% and 93.7 +/- 11.3%, respectively for saliva and gastric juice. Gel exclusion chromatography revealed hEGF-like substances, heterogeneous in size in saliva and gastric juice, the origins and physiological functions of which are unknown.
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PMID:Radioimmunoassay of epidermal growth factor in human saliva and gastric juice. 204 84

The distribution of the proopiomelanocortin-derivated amidated joining peptide (JP-N) was examined in the human pituitary gland, adrenal gland, gut and in three bronchial carcinoids. Double immunostaining showed coexistence of immunoreactive JP-N and other proopiomelanocortin derivatives, e.g., ACTH, beta-endorphin, Pro-tau-MSH, in the pituitary gland and adrenal medulla. The JP-N immunoreactive cells in the adrenal medulla were identified as a subpopulation of adrenaline-producing cells by means of an antiserum against phenylethanolamine N-methyltransferase. In the gut immunoreactive JP-N was costored with somatostatin in endocrine cells. Using radioimmunoassay, JP-N was found in higher concentrations than ACTH and alpha-MSH in the gut but not in the adrenal gland. Gel chromatography of gastric antrum and adrenal gland extracts showed three and two dominating components of immunoreactive JP-N, respectively, but under reduced conditions most of the immunoreactive material appeared as of low molecular weight in both extracts. In conclusion, immunoreactive JP-N is a major product from the processing of proopiomelanocortin in human extrapituitary tissues. The molecular forms of immunoreactive JP-N correspond to previous findings in the human pituitary gland.
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PMID:Amidated joining peptide in the human pituitary, gut, adrenal gland and bronchial carcinoids. Immunocytochemical and immunochemical evidence. 218 29


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