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)

Regulation of endocrine pancreatic hormone gene expression by cholecystokinin (CCK) was examined in the rat using cloned cDNA probes to quantify changes in specific mRNAs (insulin, glucagon, pancreatic polypeptide and somatostatin). Plasma CCK levels were raised to concentrations comparable to physiologic postprandial values either by including soybean trypsin inhibitor (SBTI) in the intraduodenal perfusate of an elemental diet (6.9 +/- 1.0 pM, n = 6), or by intravenous infusion of CCK-8 (6.0 +/- 0.9 pM, n = 6). SBTI infusion for 48 h resulted in a three- to fourfold increase in procarboxypeptidase B and kallikrein mRNA levels. Similar increases were observed when CCK was infused intravenously for 24 h. In contrast, neither SBTI intraduodenally, nor intravenous CCK had any effects on mRNA levels of insulin, glucagon, PP or somatostatin. These data therefore indicate that CCK at physiologic postprandial plasma concentrations stimulates pancreatic protease gene expression but has no effects on gene expression of endocrine pancreatic hormones.
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PMID:Effects of CCK on gene expression of endocrine pancreatic hormones. 226 71

The serine proteinase glandular kallikrein has been demonstrated in the gastrointestinal tract, although there is some doubt as to whether it is synthesized there or derives from exocrine-gland secretions. Using a rat pancreatic kallikrein cRNA probe we have demonstrated kallikrein-like gene expression in the corpus, duodenum, jejunum, ileum, caecum and colon, and compared the pattern of expression with that of the gastrointestinal peptides somatostatin, gastrin and glucagon. In addition, using a panel of oligonucleotide probes specific for various members of the rat kallikrein-gene family, we have shown that the kallikrein-like gene expressed appears to be expressed as true kallikrein.
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PMID:Kallikrein-gene expression in the rat gastrointestinal tract. 260 9

We have investigated in stimulated human pancreatic juice the presence of the following peptides: insulin, glucagon, gastrin, somatostatin, VIP and secretin. Collection of pancreatic juice (3 periods: 20 min each) was completed by endoscopic cannulation of the pancreatic duct during the infusion of secretin (0.5 U/kg/h) and cerulein (75 ng/kg/h) in 6 healthy volunteers. Pure pancreatic juice was recovered in the presence of kallikrein inhibitor (iniprol 8,000 U/ml) in refrigerated collection tubes (4 degrees C). The material was acidified, boiled for 5 min and centrifuged. Radioimmunoassays were performed on the supernatant solutions. The elution profiles on Sephadex G 25 gel filtration of the immunoreactivities were compared with standard samples of hormones, immuno-reactive insulin, glucagon and somatostatin were found in every sample: insulin was present at a constant level (50 microU/ml) during the three periods of collection; glucagon was encountered in large amounts in the first sample and decreased significantly during the subsequent periods; somatostatin which occurred at a low level during the first period was significantly increased in the following periods. Gastrin, VIP and secretin were undetectable or only inconstantly found in very small amounts. These results are in agreement with a two-directional secretion of the human pancreatic endocrine cells. The cellular origin and function of these exocrine secreted peptides need further studies.
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PMID:[Presence of hormonal polypeptides in the pure pancreatic secretion in man under stimulation by cerulein and secretin]. 286 46

The arachidonate cascade of human or rat platelets were found to be modified by peptides (bradykinin, angiotensin I, angiotensin II, Asp1-Val5-angiotensin II-amide, somatostatin) and proteases (trypsin, kallikrein). The lipoxygenase pathway was not altered by angiotensin I, angiotensin II, trypsin and kallikrein, while the synthesis some of the cyclooxygenase products was selectively changed by these substances. Bradykinin and somatostatin resulted in an attenuated formation of 12-HPETE and 12-HETE - U shape dose response curve, at the same time the synthesis of cyclooxygenase metabolites was increased - bell shape dose response curve. Asp1-Val5-angiotensin II-amide increased the synthesis of lipoxygenase products and diminished the formation of TxB2. At the same time this peptide selectively induced the enzymatic release of PGD2 from platelets. These peptides and proteolytic enzymes might have physiologic significance in the "Ying-Yang" balance in one hand between lipoxygenase and cyclooxygenase metabolites and on the other between the proaggregatory and antiaggregatory substances released from platelets.
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PMID:The action of peptides and proteases on the arachidonate cascade of human and rat platelets. 288 Apr 82

The effect of somatostatin in phalloidin-intoxicated rats was studied. Animals were given phalloidin i.p. 1.2 mg/kg (LD 90-100). Somatostatin, 250 microgram/animal, was administered i.p. in saline 5 min prior and s.c. in protamine-sulphate/ZnCl2 suspension 30 min prior and 30 min after intoxication, unless stated otherwise. In vivo and in vitro uptake studies of the toxin were performed. Liver enzymes (GPT, GLDH) and kallikrein-like activities were determined in blood obtained by orbital venipuncture. Light and electron microscopy was carried out. Somatostatin treatment led to an increase in survival rate. Of the 20 treated rats six died whereas of the 20 untreated animals 18 died. A dose dependency was proven effective when half of the initial dose of somatostatin was given. In vivo and in vitro uptake studies of the toxin demonstrate that somatostatin does not alter uptake rate by rat livers. Liver enzymes remained elevated in treated and control rats. Kallikrein-like activities showed a 61% decline in treated animals whereas they rose up to 120% in controls as compared to pretreatment conditions. Light and electron microscopy reveals less severe lesions in somatostatin-treated animals. A possible interaction of somatostatin in shock development is discussed, phalloidin seems to be a suitable tool for further investigations concerning cell protection by somatostatin.
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PMID:Beneficial effect of somatostatin in phalloidin-intoxicated rats. Influence on survival rate, biochemical and morphological data, and 3H-demethylphalloin absorption rate by the liver. 611 83

It is well known that there are functional and morphological similarities between the salivary glands and the pancreas. Amylase, kallikrein and glucagon are present in both tissues. Morphological similarities of the two tissues have been observed by using a light and electron microscope. In order to examine the pathophysiological relationship between the pancreas and the salivary glands, an immunohistochemical study using antisera against proline-rich peptide P-C, which was recently isolated from human whole saliva, was carried out on the human salivary glands and the pancreas. Peptide P-C like immunoreactivity was found not only in the salivary glands but also in the pancreatic islets. Furthermore, observation of serial thin sections immunostained with insulin, glucagon, somatostatin, PP antisera and antisera against peptide P-C revealed that peptide P-C like immunoreactivity-containing cells were identical to insulin containing B-cells. As the antisera against peptide P-C did not have any cross-reactivity to other kinds of peptide including insulin, glucagon, somatostatin, pp, VIP, human C-peptide and kallikrein, the present finding suggests that peptide P-C like immunoreactivity is present in the B-cells independently of insulin and proinsulin. The finding seems to be a new addition to the lists of proof which support the presence of a pathophysiological relation between the salivary glands and the pancreas. Although it seems likely that peptide P-C like immunoreactivity in the pancreatic B-cells may play some role in the function of the B-cells, since this material was present only in the B-cells among four kinds of cells in the pancreatic islets, its exact pathophysiological role remains to be elucidated.
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PMID:[The presence of proline-rich peptide P-C like immunoreactivity in the human pancreatic B-cells]. 634 34

Antisera against proline rich peptide P-C, recently isolated from human whole saliva were raised in rabbits by injections of peptide P-C-BSA conjugates. Immunohistochemical study using the antisera was carried out on human salivary glands, gut and pancreas. The results showed that peptide P-C like immunoreactivity was present not only in the salivary glands but also in the pancreatic islets, though not in the gut. Furthermore, immunostaining of adjacent thin sections revealed that cells reacting with antisera against peptide P-C were identical to those reacting with insulin antisera. As the antisera against peptide P-C did not have any cross-reactivities to insulin, glucagon, somatostatin, pancreatic polypeptide, VIP and human C-peptide, the antisera were considered to recognize specifically either peptide P-C related antigen or peptide P-C itself in human pancreatic B-cells. A novel substance, peptide P-C like immunoreactivity, may be present in pancreatic B-cells independent of pro-insulin and insulin. Morphological similarity between the salivary glands and the pancreas has been reported, and amylase, kallikrein and glucagon are present in both. These findings seem to suggest some functional relation between the pancreas and salivary glands. Detection of peptide P-C like immunoreactivity in the pancreas and salivary glands would be a additional support for this idea. Although it is suggested that peptide P-C like immunoreactivity in pancreatic B-cells may play some role in the function of B-cells, its exact pathophysiological role remains obscure.
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PMID:Immunohistochemical demonstration of salivary proline rich peptide P-C like immunoreactivity in human pancreatic B-cells. 635 25

Hyperamylasemia after endoscopic sphincterotomy is a common event, occurring in about 70% of cases. Clinical acute pancreatitis may also develop in 1% to 6% of cases. Previous attempts to prevent this reaction with inhibitors of exocrine pancreatic secretion (somatostatin and octreotide) provided conflicting and often disappointing results. Kallikrein is one of the proteases that sustain the inflammatory process in acute pancreatitis; the C1 inhibitor is the only physiologic inhibitor of the first component of the human complement cascade and is a major inactivator of kallikrein and Factor XII. Therefore, we tested the C1 inhibitor in the prevention of hyperamylasemia in 40 consecutive patients undergoing endoscopic sphincterotomy for common bile duct stones or benign papillary stenosis. They were given either C1 inhibitor (20 cases) or placebo (20 cases) before the procedure. Serum amylase levels were determined at baseline and 2, 4, 8, and 24 hours thereafter. Significant differences in serum amylase levels between groups were observed at 2 hours (p < .01), 4 hours (p < .0005), and 8 hours (p < .005) after sphincterotomy. The differences in amylase levels were also significant among the 24 subjects with pancreatic ductal filling (2 hours, p < .05; 4 hours, p < .005; 8 hours, p < .01) and the 9 patients with previous episodes of acute pancreatitis (4 hours, p < .05; 8 hours, p < .05; 24 hours, p < .05). The infusion of C1-inhibitor plasma concentrate resulted in a 50% increase in functional levels of C1 inhibitor (in the 8 cases for whom they were assayed), which persisted throughout the observation period.
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PMID:Infusion of C1-inhibitor plasma concentrate prevents hyperamylasemia induced by endoscopic sphincterotomy. 853 96

Somatostatin-(1-14) was hydrolysed by human tissue kallikrein at the Phe7-Trp8 bond, after a Phe-Phe pair of amino acids, with similar kinetic parameters to those described for human high- and low-molecular-mass kininogens. Substance P and human insulin, which also contain a Phe-Phe pair in their sequences, were both resistant. More details of this hydrolytic specificity of human tissue kallikrein were obtained by synthesizing and assaying internally quenched fluorescent peptides containing the sequence of somatostatin-(1-14), as well as the reactive-centre loop of human kallikrein-binding protein (kallistatin). We also observed that human tissue kallikrein hydrolysed growth hormone-releasing hormone at the Arg11-Lys12 bond, although this peptide contains in its structure a pair of leucines (Leu22-Leu23), in contrast with the Phe-Phe pair in somatostatin. We have also demonstrated the susceptibility to human tissue kallikrein of some chromogenic peptide s with the general structure of X-Phe-Phe-p-nitroanilide and D-Pro-Phe-Phe-4-methylcoumaryl-7-amide.
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PMID:Hydrolysis of somatostatin by human tissue kallikrein after the amino acid pair phe-Phe. 935 30

We have explored in detail the determinants of specificity for the hydrolysis by human tissue kallikrein (hK1) of substrates containing the Phe-Phe amino acid pair, after which hK1 cleaves kallistatin (human kallikrein-binding protein), a specific serpin for this protease, as well as somatostatin 1-14. Internally quenched fluorogenic peptides were synthesized with the general structure Abz-peptidyl-EDDnp [Abz, o-aminobenzoic acid; EDDnp, N-(2, 4-dinitrophenyl)ethylenediamine], based on the natural reactive-centre loop sequence of kallistatin from P9 to P'13, and the kinetic parameters of their hydrolysis by hK1 were determined. All these peptides were cleaved after the Phe-Phe pair. For comparison, we have also examined peptides containing the reactive-centre loop sequences of human protein-C inhibitor (PCI) and rat kallikrein-binding protein, which were hydrolysed after Phe-Arg and Leu-Lys bonds, respectively. Hybrid peptides containing kallistatin-PCI sequences showed that the efficiency of hK1 activity on the peptides containing kallistatin and PCI sequences depended on both the nature of the P1 amino acid as well as on residues at the P- and P'-sides. Moreover, we have made systematic modifications on the hydrophobic pair Phe-Phe, and on Lys and Ile at the P3 and P4 positions according to the peptide substrate, Abz-AIKFFSRQ-EDDnp. All together, we concluded that tissue kallikrein was very effective on short substrates that are cleaved after the Phe-Arg pair; however, hydrolysis after Phe-Phe or other hydrophobic pairs of amino acids was more restrictive, requiring additional enzyme-substrate interaction and/or particular substrate conformations.
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PMID:Specificity of human tissue kallikrein towards substrates containing Phe-Phe pair of amino acids. 1019 Dec 81


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