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

The expression of somatostatin mRNA within the allocortex of the rat was examined by in situ hybridization with an alkaline phosphatase labeled probe. We sought to determine whether parcellation of the allocortex could be based upon the number and laminar location of the hybridized cells and to contrast the allocortical features with those of the isocortical areas. The cingulate region was characterized by intense, moderate, and faint cells, small to medium in size throughout the laminae. The retrosplenial region demonstrated a somewhat stratified appearance with an abundance of cells expressing somatostatin mRNA in the upper portion of the composite layer II-IV and also in the upper portion of layer VI. The insular region displayed more heterogeneity. The distribution of the cells hybridized for somatostatin mRNA formed distinctive configurations within the insular region (dorsal and ventral agranular insular areas) with no obvious generality. The perirhinal area resembled the ventral agranular insular area, and the cell distribution of the entorhinal and prepiriform areas displayed a common characteristic in that the primary axis of the perikarya of somatostatin mRNA expressing cells within the lower layers were oriented at almost every possible angle. The conclusion of the investigation is that in situ hybridization for somatostatin mRNA provides a means by which the areal boundaries within the allocortex may be drawn.
 ...
PMID:In situ hybridization for somatostatin mRNA in the adult rat: cingulate, insular, prepiriform, perirhinal, entorhinal, and retrosplenial cortical regions. 869 74

Somatostatin modulates gastrointestinal mucosal growth and differentiation indirectly via inhibition of bioactive peptides and directly by less well understood mechanisms. We studied the direct effects of the somatostatin analog octreotide on proliferation, brush-border enzyme activity, cell-matrix interactions and intracellular cAMP in Caco-2 human intestinal epithelial cells. Proliferation was assessed by cell counting and [3H]thymidine uptake. The brush-border enzymes alkaline phosphatase (AP) and dipeptidyl dipeptidase (DP) were quantitated by synthetic substrate digestion. Adhesion and migration on purified matrix proteins were also measured. Octreotide (10(-9)-10(-5)M) shortened doubling time (46.5 +/- 6.2% at 10(-5) M, n = 20, P < 0.0001) and stimulated [3H]thymidine uptake. Octreotide decreased intracellular cAMP by 19.4 +/- 5.0% (n = 7, P < 0.0001) while dibutyryl-cAMP (10(-6) M) prolonged doubling time by 10.1 +/- 1.5% (n = 8, P < 0.0001), and blocked the octreotide effect. Octreotide decreased AP and DP with maximal effect at 10(-6) M (36.8 +/- 8.3% and 20.5 +/- 9.1%, n > 7, P < 0.0005 respectively). However, mitomycin proliferative blockade prevented octreotide inhibition of AP and DP, suggesting that the mitogenic effects of octreotide had simply decreased average maturity of the cells. Octreotide did not alter Caco-2 adhesion, EGF-or matrix-modulated motility, or integrin surface expression. Octreotide appears to directly stimulate Caco-2 proliferation by decreasing cAMP. These proliferative effects modulate Caco-2 differentiation but do not affect cell-matrix interactions.
 ...
PMID:Octreotide differentially modulates human Caco-2 intestinal epithelial cell proliferation and differentiation by decreasing intracellular cAMP. 870 Oct 39

1. In search of methods to identify bio-active ligands specific for G protein-coupled receptors with seven transmembrane spanning regions, we have developed a filamentous phage-based selection and functional screening method. 2. First, methods for panning peptide phage on cells were established, using the hormone somatostatin as a model. Somatostatin was displayed on the surface of filamentous phage by cloning into phage(mid) vectors and fusion to either pIII or pVIII viral coat proteins. Peptide displaying phage bound to a polyclonal anti-somatostatin serum, and, more importantly, to several somatostatin receptor subtypes (Sst) expressed on transfected CHO-K1 cells, in a pattern which was dependent on the used display method. Binding was competed with somatostatin, with an IC50 in the nanomolar range. The phage were specifically enriched by panning on cells, establishing conditions for cell selections of phage libraries. 3. Binding of somatostatin displaying phage to sst2 on a reporter cell line, in which binding of natural ligand reduces secretion of alkaline phosphatase (via a cyclic AMP responsive element sensitive promoter), proved that the phage particles act as receptor-specific agonists. Less than 100 phage particles per cell were required for this activity, which is approximately 1000 fold less than soluble somatostatin, suggesting that phage binding interferes with normal receptor desensitization and/or recycling. 4. The combination of biopanning of phage libraries on cells with functional screening of phage particles for receptor triggering activity, may be used to select novel, bio-active ligands from phage libraries of random peptides, antibody fragments, or libraries based on the natural receptor ligand.
 ...
PMID:Somatostatin displayed on filamentous phage as a receptor-specific agonist. 977 37

The purpose of this study was to examine the effect of endogenous somatostatin hormone on bacterial translocation in obstructive jaundiced rats. Five groups of rats were studied: group I (n = 10), non-operated group (control); group II (n = 10), sham-operated group which underwent laparotomy and dissection of portal elements, while the common bile duct was not ligated and somatostatin was not injected; group III (n = 10), same as group II, plus injection of somatostatin; group IV (n = 10), common bile duct was ligated with laparotomy but somatostatin was not injected; group V (n = 10), same as group IV, plus somatostatin injection. The blood was analyzed for somatostatin, alkaline phosphatase, and bilirubin levels on the third and tenth days in all animals. At study termination (tenth day), peritoneal swab and blood cultures were taken, and liver, spleen, lung, and mesenteric lymph nodes were harvested for microbiological studies. Bacterial translocation levels were higher in groups III, IV, and V when compared with levels in groups I and II. Similar translocation levels were obtained when blood somatostatin levels were comparable. However, the highest translocation rate was found in groups IV and V in which the blood somatostatin level was also higher when compared with that in other groups. This finding shows that blood somatostatin level is increased in obstructive jaundice. This may explain the bacterial translocation and related sepsis found in obstructive jaundice.
 ...
PMID:Somatostatin: possible cause of bacterial translocation in obstructive jaundiced rats. 1066 91

We evaluated whether the combination of triptorelin, a LHRH analog (LHRH-A), with dexamethasone and lanreotide, a somatostatin analog, can produce objective clinical responses in metastatic androgen ablation-refractory prostate cancer (stage D3) patients who have relapsed, after combined androgen blockade (LHRH-A plus antiandrogen) and antiandrogen withdrawal. Eleven stage D3 patients with diffuse bony metastases, who had progressed despite initial responses (lasting <12 months) to combined androgen blockade therapy and subsequently failed antiandrogen withdrawal, received oral dexamethasone (4 mg daily for the first month, tapered down to 2 mg after the first month and 1 mg after the second month, and continued on 1 mg thereafter) and lanreotide (30 mg im every 14 d) in combination with triptorelin (3.75 mg im every 28 d). Serum prostate-specific antigen, alkaline phosphatase, performance status, and bone pain were assessed monthly during therapy. Fasting blood glucose was measured biweekly, and serum IGF-I, T, and dehydroepiandrosterone sulfate levels were assessed at baseline, at response to the combination therapy, and at relapse from it. Ten of 11 stage D3 patients [90.9% of patients; 95% confidence interval (CI), 58.7-99.8%] had durable objective clinical responses (including > or = 50% prostate-specific antigen decline in 8 patients, 72.7%; 95% CI, 39-94%). All patients reported significant and durable improvement of bone pain (for a median duration of 13 months; 95% CI, 12-14 months; range, 6-22 months) and performance status (median duration, 19 months; 95% CI, 13-25 months; range, 7-22 months) without major treatment-related side effects. The median progression-free survival was 7 months (95% CI, 4-10 months; range, 3-17 months), and the median overall survival was 18 months (95% CI, 16-20 months; range, 7-22 months). Five of six total deaths occurred secondary to disease progression. We observed a statistically significant (P = 0.018) reduction in serum IGF-I levels at response to the combination therapy (60% reduction of baseline IGF-I levels). Dehydroepiandrosterone sulfate levels, although already significantly suppressed at baseline, had an additional significant reduction (P < 0.02) at response to therapy. T levels remained suppressed within castration levels (<3 nmol/liter, at baseline and throughout therapy, including relapse). The combination therapy of LHRH-A with dexamethasone plus somatostatin analog produces objective clinical responses and symptomatic improvement in androgen ablation (LHRH-A) refractory prostate cancer patients.
 ...
PMID:A combination therapy of dexamethasone and somatostatin analog reintroduces objective clinical responses to LHRH analog in androgen ablation-refractory prostate cancer patients. 1173 29

Tissue kallikreins are thought to be present in the pancreatic islets of Langerhans and to aid in the conversion of proinsulin to insulin. In recent immunohistochemical studies, we observed strong staining of the newly identified human kallikreins 6 and 10 (hK6 and hK10) in the islets of Langerhans. Here, we examine hK6 and hK10 immunoexpression in different types of islet cells of the endocrine pancreas, in order to obtain clues for hK6 and hK10 function in these cells. Ten cases of normal pancreatic tissue, two cases of nesidioblastosis, five insulin-producing tumours and one case of multiple endocrine neoplasia 1 syndrome, containing an insulin-, a somatostatin- and several glucagon-producing tumours, as well as tiny foci of endocrine dysplasia with different predominance of the secreted hormones (mainly glucagon and pancreatic polypeptide) were included in the study. A streptavidin--biotin--peroxidase and an alkaline phosphatase protocol, as well as a sequential immunoenzymatic double staining method were performed, using specific antibodies against hK6, hK10, insulin, glucagon, somatostatin, pancreatic polypeptide, and serotonin. hK6 and hK10 immunoexpression was observed in the islets of Langerhans, including the pancreatic polypeptide-rich islets, in the normal pancreas. Scattered hK6 and hK10 positive cells were localized in relationship with pancreatic acinar cells. In the exocrine pancreas, a cytoplasmic and/or brush border hK6 and hK10 immunoexpression was observed in the median and small sized pancreatic ducts, while the acinar cells were negative. Foci of nesidioblastosis and endocrine dysplasia expressed both kallikreins. hK6 and hK10 were also strongly and diffusely expressed throughout all insulin-, glucagon- and somatostatin-producing tumours. The double staining method revealed co-localization of each hormone and hK6/hK10 respectively, in the same cellular population, in the normal as well as in the diseased pancreas. Our results support the view that hK6 and hK10 may be involved in insulin and other pancreatic hormone processing and/or secretion, as well as in physiological functions related to the endocrine pancreas.
 ...
PMID:Immunohistochemical localization of human kallikreins 6 and 10 in pancreatic islets. 1276 63

The somatostatin analogue lanreotide is effective in reducing growth hormone levels in patients with acromegaly. Acromegaly is characterized by calcium homeostasis alterations. The aim of our study was to evaluate the effects of lanreotide on bone turnover markers in a group of acromegalic patients and to verify a possible increase of intact parathormone (iPTH) levels in a transient or persistent way. Serum GH, IGF-I and serum and urinary markers of bone metabolism were measured before treatment and on months 3 and 24. In short-term treatment (3 months), lanreotide significantly decreased GH, IGF-I, serum calcium, osteocalcin and alkaline phosphatase levels, but increased iPTH level (49 +/- 16.7 vs pre-treatment 28.3 +/- 7.6 ng/L, p<0.001). During long-term study (24 months) GH and IGF-I were significantly still low; serum calcium and alkaline phosphatase levels returned to pre-treatment levels. iPTH level was significantly still higher compared with pre-treatment (46.4 +/- 9.2 vs 28.3 +/- 7.6 ng/L, p<0.05). No changes were seen in serum albumin, creatinine and vitamin D during short and long term treatment. The changes of most bone markers during lanreotide treatment can be explained by the decrease of GH and IGF-I. The increase of iPTH concentration suggests that lanreotide has ulterior and long-standing actions on calcium homeostasis: intestinal malabsorption of calcium due to the lanreotide could contribute to this "secondary" hyperparathyroidism. The clinical relevance of these long-standing effects needs to be further investigated.
 ...
PMID:Long-term treatment of acromegaly with lanreotide: evidence of increased serum parathormone concentration. 1564 68

The effect of cysteamine, a specific somatostatin depletor, on biliary secretion was studied in urethane-anesthetized rats. Different groups of rats received ip cysteamine at 25, 100 or 340 mg/kg just before bile collection commenced. Other groups of rats were pretreated with cysteamine (340 mg/kg ip) at 4 or 24 h prior to bile duct cannulation and bile collection. Bile secretions were collected at 30-min intervals for 4 h after bile duct cannulation. Total proteins, cholesterol, total lipids, glucose and several hepatic enzymes were assessed in bile. Results indicated that basal bile secretion was only slightly reduced and tended to decrease after drug administration (13% decrease after 340 mg/kg). Cysteamine induced dose-dependent decrease in protein secretion, and the maximum effect was reached at a dose of 340 mg/kg. The effect of cysteamine on protein secretion was prolonged, since it was still observed 24 h after the treatment with cysteamine. Cholesterol and lipid secretion was inhibited by 52.5 and 42.5%, respectively, by the drug, with the latter effect being evident 24 h after drug administration. In addition, the drug inhibited biliary glucose and aspartate aminotransferase concentrations, but increased that of alkaline phosphatase. The results suggest that acute administration of cysteamine inhibits protein, cholesterol and lipid secretion into bile.
 ...
PMID:Effect of cysteamine on bile secretion in the rat. 1598 17

Oncogenic osteomalacia is a rare paraneoplastic syndrome of acquired hypophosphatemic osteomalacia, resulting from a deficit in renal tubular phosphate reabsorption, in which fibroblast growth factor 23 (FGF23) seems to be implicated. This condition is usually associated with a phosphaturic mesenchymal tumor of mixed connective tissue located in the bone or soft tissue. The clinical and the radiologic findings are the same as those seen in osteomalacia, and the biochemical features include renal phosphate loss, low serum phosphate and 1,25-(OH)(2) vitD(3) levels, increased alkaline phosphatase, and normal calcium, PTH, calcitonin, 25-OH-vitD(3) and 25,25-(OH)(2) vitD(3). We present two cases of oncogenic osteomalacia associated with phosphaturic mesenchymal tumors, which were histologically similar, but presented a completely different evolution. In the first patient, the tumor developed on the sole of the foot. Following removal of the mass, the symptoms resolved and biochemical and radiological parameters returned to normal. However, in the second patient, a liver tumor developed and resection did not resolve the disease. Multiple lesions appeared in several locations during follow-up. This disease usually remits with complete tumor resection. Nevertheless, if this is not possible, oral treatment with phosphate, calcium and calcitriol can improve the symptoms. If scintigraphy of the tumor shows octreotide receptors, patients may respond partially to therapy with somatostatin analogs, with stabilization of the lesion.
 ...
PMID:Oncogenic osteomalacia: two case reports with surprisingly different outcomes. 1912 58

Null mutant mice lacking the transcription factor pancreatic and duodenal homeobox 1 (Pdx1) are apancreatic and survive only a few days after birth. The role of Pdx1 in regulating intestinal gene expression has therefore yet to be determined in viable mice with normal pancreatic development. We hypothesized that conditional inactivation of Pdx1 restricted to the intestinal epithelium would alter intestinal gene expression and cell differentiation. Pdx1(flox/flox);VilCre mice with intestine-specific Pdx1 inactivation were generated by crossing a transgenic mouse strain expressing Cre recombinase, driven by a mouse villin 1 gene promoter fragment, with a mutant mouse strain homozygous for loxP site-flanked Pdx1. Pdx1 protein is undetectable in all epithelial cells in the intestinal epithelium of Pdx1(flox/flox);VilCre mice. Goblet cell number and mRNA abundance for mucin 3 and mucin 13 genes in the proximal small intestine are comparable between Pdx1(flox/flox);VilCre and control mice. Similarly, Paneth cell number and expression of Paneth cell-related genes Defa1, Defcr-rs1, and Mmp7 in the proximal small intestine remain statistically unchanged by Pdx1 inactivation. Although the number of enteroendocrine cells expressing chromogranin A/B, gastric inhibitory polypeptide (Gip), or somatostatin (Sst) is unaffected in the Pdx1(flox/flox);VilCre mice, mRNA abundance for Gip and Sst is significantly reduced in the proximal small intestine. Conditional Pdx1 inactivation attenuates intestinal alkaline phosphatase (IAP) activity in the duodenal epithelium, consistent with an average 91% decrease in expression of the mouse enterocyte IAP gene, alkaline phosphatase 3 (a novel Pdx1 target candidate), in the proximal small intestine following Pdx1 inactivation. We conclude that Pdx1 is necessary for patterning appropriate gene expression in enterocytes and enteroendocrine cells of the proximal small intestine.
 ...
PMID:Pdx1 inactivation restricted to the intestinal epithelium in mice alters duodenal gene expression in enterocytes and enteroendocrine cells. 1980 54


<< Previous 1 2 3 4 5 Next >>