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)

We have studied the in vitro TSH secretion and the adenylate cyclase (AC) activity of a human pituitary adenoma surgically removed from a hyperthyroid patient showing high serum TSH levels. The tumor appeared almost homogeneously constituted by cells positive for an anti-TSH-beta antiserum and showing the ultrastructural characteristics of the adenomatous thyrotrophs. Adenoma fragments released in vitro a large amount of TSH (148.4 microU/mg prot/30 min), alpha-subunit (35.5 ng/mg prot/30 min) and TSH-beta (10.1 ng/mg prot/30 min). The effects of somatostatin (GHRIH) and dopamine (DA) on the hormone release have been tested in vitro. Both agents markedly inhibited the release of intact TSH and TSH-beta whereas the release of alpha-subunit was less affected. The two agents were effective at concentrations higher than 10(-8)M. The ability of GHRIH and DA in modulating the AC activity was investigated in membrane fraction preparations. GHRIH inhibited AC at concentrations higher than 10(-7)M. The maximal inhibition was 32% at 10(-5)M. Conversely, DA slightly stimulated AC activity. This effects was not mimicked by the dopaminergic ergot CH 29-717, which was completely ineffective on the enzyme. These results suggest that: 1) in this TSH-secreting pituitary adenoma a normal secretory response to the inhibiting agents (GHRIH and DA) is present; 2) different mechanisms of transduction of the GHRIH and DA signals (cAMP dependent and cAMP independent) could be operating in this tumor.
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PMID:In vitro studies on TSH secretion and adenylate cyclase activity in a human TSH-secreting pituitary adenoma. Effects of somatostatin and dopamine. 286 99

A total of 49 gastric tubular adenomas and 6 tubular adenomas with foci of adenocarcinoma from surgically resected stomachs were examined histologically and immunohistochemically for gut peptide hormones, serotonin, carcinoembryonic antigen (CEA), secretory component (SC), and lysozyme. A variety of endocrine cells were detected in tubular adenoma with mild to moderate atypia. Both the frequency and distribution density were highest for serotonin-containing EC cells, often showing hyperplasia, followed by glicentin-containing L cells, somatostatin-containing D cells and motilin-containing Mo cells in the order given. Adenoma cells with SC immunoreactivity were more dominant than those with CEA immunoreactivity. In tubular adenoma with severe atypia, endocrine cells were markedly decreased, whereas adenoma cells with CEA immunoreactivity were increased. The distribution density of lysozyme-containing cells in tubular adenoma of the intermediate zone and fundus was significantly higher than that of the antrum. In the subjacent mucosa of the adenoma, L cells and SC-positive epithelial cells were detected in 24 and 33 cases, respectively. These findings suggest that gastric tubular adenoma develops from intestinal metaplasia. In addition, gastric tubular adenoma showed a tendency to lose various intestinal markers with increase of histologic atypicality.
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PMID:Tubular adenoma of the human stomach. An immunohistochemical analysis of gut hormones, serotonin, carcinoembryonic antigen, secretory component, and lysozyme. 353 Apr 27

This study investigated quantitated expression of dopamine 2 receptor (D2R) and somatostatin receptors of the five types (SSTR1-SSTR5) in a large series of clinically non-functioning pituitary adenomas (CNFAs). Co-expression of these receptors in individual adenomas was studied as well as correlation between receptor types. Adenoma tissue from 198 patients who underwent surgery for CNFAs was analyzed by immunohistochemistry and quantitative real-time PCR. D2R and SSTR1-3 mRNA was expressed in all 198 adenomas. SSTR4 and SSTR5 were detectable in 85 % and 61 % of adenomas, respectively. Expression of D2R was significantly higher than that of the somatostatin receptors. The median relative expressions were as follows from highest D2R >> SSTR3 > SSTR2 > SSTR1 > SSTR5 > SSTR4. High relative expression (ratio to beta-glucuronidase mRNA > 1) of D2R was found in 60 % of tumors, high expression of SSTR1 in 7.5 %, SSTR2 in 7 %, SSTR3 in 4 % and SSTR5 in 0.5 %. The quantity of D2R correlated positively with expression of SSTR2 and SSTR3, and negatively with SSTR1 and SSTR5. Among histological adenoma types, SSTR1 was significantly higher in null-cell adenomas and SSTR3 was lower in silent corticotroph adenomas. In conclusions, in CNFAs, high expression of somatostatin receptors is much less common than that of D2R, and co-expression of both these receptors is exceptional. D2R and SSTR3 seem to be the most promising targets for pharmacological treatment.
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PMID:Dopamine 2 and somatostatin 1-5 receptors coexpression in clinically non-functioning pituitary adenomas. 2553 18