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)

Patients with hyperthyroidism have reduced spontaneous and stimulated growth hormone (GH) secretion. The aim of our study was to evaluate the effects of galanin, a novel neuropeptide which stimulates GH secretion in man, on the GH response to GHRH in patients with hyperthyroidism. Eight untreated hyperthyroid patients with Graves' disease (6F, 2M, aged 25-50 years) and six healthy volunteers (3F, 3M, aged 27-76 years) underwent from -10 to 30 min in random order: (i) porcine galanin, iv, 500 micrograms in 100 ml saline; or (ii) saline, iv, 100 ml. A bolus of human GHRH(1-29)NH2, 100 micrograms, was injected iv at 0 min. Hyperthyroid patients showed blunted GH peaks after GHRH+saline (10.2 +/- 2.5 micrograms/l) compared to normal subjects (20.7 +/- 4.8 micrograms/l, p < 0.05). GH peaks after GHRH+galanin were also significantly lower in hyperthyroid subjects (12.5 +/- 3 micrograms/l) compared to normal subjects (43.8 +/- 6 micrograms/l, p < 0.05). That galanin is not able to reverse the blunted GH response to GHRH in hyperthyroidism suggests that hyperthyroxinemia may either increase the somatostatin release by the hypothalamus or directly affect the pituitary GH secretory capacity.
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PMID:Galanin does not affect the growth hormone-releasing hormone-stimulated growth hormone secretion in patients with hyperthyroidism. 128 76

Patients with hyperthyroidism have reduced GH responses to pharmacological stimuli and reduced spontaneous nocturnal GH secretion. The stimulatory effect of arginine on GH secretion has been suggested to depend on a decrease in hypothalamic somatostatin tone. The aim of our study was to evaluate the effects of arginine on the GH-releasing hormone (GHRH)-stimulated GH secretion in patients with hyperthyroidism. Six hyperthyroid patients with recent diagnosis of Graves' disease [mean age +/- SEM, 39.2 +/- 1.4 years; body mass index (BMI) 22 +/- 0.4 kg/m2] and 6 healthy nonobese volunteers (4 males, 2 females; mean age +/- SEM, 35 +/- 3.5 years) underwent two experimental trials at no less than 7-day intervals: GHRH (100 micrograms, i.v.)-induced GH secretion was evaluated after 30 min i.v. infusion of saline (100 ml) or arginine (30 g) in 100 ml of saline. Hyperthyroid patients showed blunted GH peaks after GHRH (13.2 +/- 2.9 micrograms/l) as compared with normal subjects (23.8 +/- 3.9 micrograms/l, p < 0.05). GH peaks after GHRH were only slightly enhanced by arginine in hyperthyroid subjects (17.6 +/- 2.9 micrograms/l), whereas, in normal subjects, the enhancement was clear cut (36.6 +/- 4.4 micrograms/l; p < 0.05). GH values after arginine + GHRH were still lower in hyperthyroid patients with respect to normal subjects. Our data demonstrate that arginine enhances but does not normalize the GH response to GHRH in patients with hyperthyroidism when compared with normal subjects. We hypothesize that hyperthyroxinemia may decrease GH secretion, both increasing somatostatin tone and acting directly at the pituitary level.
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PMID:Effect of arginine on the GHRH-stimulated GH secretion in patients with hyperthyroidism. 130 47

A 40-year-old woman, who had previously received radioactive iodine for hyperthyroidism, presumably due to Graves' disease, subsequently was found to have inappropriately elevated serum TSH and alpha-subunit levels and a pituitary adenoma. Detailed clinical studies revealed marked serum TSH elevations (approximately 100 mU/L) with no circadian variation, but with 7 pulses/24 h. Serum alpha-subunit levels averaged 2.5 micrograms/L, with 13 pulses/24 h. Neither serum TSH nor alpha-subunit responded to TRH stimulation, nor did serum TSH change during dopamine infusion, but alpha-subunit levels did decline slightly. In contrast, during somatostatin infusion, serum TSH declined to 30% of baseline levels, while alpha-subunit levels did not change. Pituitary adenoma tissue obtained at the time of transsphenoidal surgery immunostained weakly with anti-TSH beta serum and strongly with anti-alpha-subunit serum. Northern blot analysis of RNA isolated from the tumor revealed TSH beta and alpha-subunit mRNA levels of normal length, while primer extension analysis showed a major initiation site for the TSH beta gene that appeared to be identical in the tumor and normal pituitary tissue. A second minor upstream start site was detected in the tumor, but it represented less than 1% of transcription compared to the major downstream start site. We conclude that the tumor secreted TSH and alpha-subunit in an abnormal and discordant fashion, but that the TSH gene initiation site appeared to be normal and, therefore, did not explain the observed secretory abnormalities.
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PMID:Clinical and molecular studies of a thyrotropin-secreting pituitary adenoma. 272 29

Increased pancreatic somatostatin (somatotrophin release inhibiting factor (SRIF) has been found in hypothyroid rats. Therefore, we wanted to investigate plasma SRIF in patients with hypo- and hyperthyroidism. Two groups of patients, 7 cases with autoimmune hypothyroidism, 31-75 years old, and 7 cases with Graves' disease, 19-43 years old, were compared with regard to plasma SRIF before, during and after an arginine infusion (0.5 g/kg/20 min). None of the patients suffered from diabetes mellitus or obesity. Plasma SRIF was higher in the hypothyroid patients (mean basal value 21.5 +/- 3.9, peak value 28.7 +/- 5.1 pmol/l) compared with the hyperthyroid group (mean basal value 11.6 +/- 3.3, peak value 16.2 +/- 4.0 pmol/l). The hypothyroid group also had significantly higher serum insulin values during arginine stimulation. No difference was found in plasma glucagon, serum growth hormone (GH) or blood glucose. In conclusion, plasma SRIF is elevated in primary hypothyroidism compared with hyperthyroidism. The reason for this finding is uncertain, but a reduced SRIF clearance is a possible explanation. The association of our findings with the reduced glucose tolerance in hyperthyroidism is discussed.
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PMID:Plasma somatostatin is elevated in primary hypothyroidism compared with hyperthyroidism. 287 May 98

Five women with Graves' disease, 26-52 years of age, with serum concentrations of triiodothyronine (T3) 4.8-9.2 nmol/l and thyroxine (T4) 200-320 nmol/l were studied. A 26 h infusion of cyclic somatostatin (Bachem), 6 mg in isotonic saline solution was administered. Radioactive iodine i.v. (125I or 131I) was given immediately after the start of this infusion. Serum T3, T4 and conversion rate (CR% = PBRI: total RI X 100) were determined four times during the infusion, then daily for a week. The same studies, related to an injection of radioiodine, were performed during a control week when no somatostatin was administered. Arginine-stimulated insulin and growth hormone (hGH) concentrations were considerably lowered by the somatostatin infusion. No difference in serum T3, T4 or CR between the week that started with somatostatin infusion and the control week was observed. Twelve-26 h after the somatostatin infusion started, all patients experienced gastrointestinal symptoms, which lasted 2-6 h after somatostatin withdrawal. Somatostatin in the dose given does not inhibit thyroid gland function in Graves' disease.
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PMID:Lack of effect of somatostatin on thyroid gland function in Graves' disease. 610 71

In the past, pituitary tumours that produce one or more of the glycoproteins (TSH, LH, FSH and alpha subunit) were thought to be rare. However, using modern immunocytochemical and molecular biology techniques, these tumours are being recognized with increasing frequency. Many of these tumours produce glycoprotein alpha and beta subunits in addition to intact glycoproteins. Hormone production is often low compared with tumour size, and serum hormone levels may not be elevated in these patients. Tumours that produce the gonadotrophins (LH or FSH) or alpha subunit account for the majority of clinically non-functioning pituitary adenomas. They do not cause a specific clinical syndrome, and usually present with symptoms of a large mass lesion and/or hypopituitarism. Optimal treatment of these tumours is often difficult. The initial approach is usually transsphenoidal surgery, followed by radiation therapy if there are symptoms due to residual tumour. Medical therapy of gonadotrophin and alpha subunit tumours may include the use of dopamine agonists or somatostatin analogues, although neither has been shown to consistently decrease tumour size. Preliminary trials with experimental GnRH antagonists suggest that these agents may be useful as adjuvant therapy of gonadotrophin tumours. Tumours that produce TSH are rare. Patients present with hyperthyroidism, which is often misdiagnosed as Graves' disease, as well as with symptoms of a pituitary mass lesion. Almost all TSH tumours secrete excess amounts of free alpha subunit. Optimal treatment of these tumours includes transsphenoidal surgery, followed by radiation therapy for residual tumour. The somatostatin analogue octreotide is effective in reducing excess TSH secretion from these tumours, and causes a reduction in tumour volume in a significant minority of patients.
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PMID:Glycoprotein-secreting pituitary adenomas. 762 88

Somatostatin receptor scintigraphy with 111In-labeled octreotide proves to be a very sensitive diagnostic tool for evaluation of inflammative activity in endocrine ophthalmopathy (EO). The results of somatostatin receptor scintigraphy (SRS) in 40 patients with EO show a high orbital accumulation of 111In-octreotide in clinically active EO (4 h-median/orbit-brain-ratio: 12.6; controls 4 h-median: 5.8) Patients with clinically inactive EO (4 h-median: 7.1) show a similar orbital accumulation of radioactivity compared to controls. 5 patients with active orbital myositis also revealed an even higher orbital accumulation of radioactivity (4 h-median: 42.3). The diagnostic value of SRS lies in its ability to act as a measure of inflammation and can be useful as an activity parameter when planning therapeutic procedure as well as for EO follow-up. The results in patients with orbital myositis nevertheless do not permit a differential diagnosis with this method. The therapeutic value of 111In-octreotide in Graves' disease has yet to be established.
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PMID:[Somatostatin receptor scintigraphy in endocrine orbitopathy]. 780 69

Visualization of malignant lymphomas and granulomatous disease is possible by [111In-DTPA-D-Phe1]octreotide scintigraphy through binding of the radioligand to somatostatin receptors on activated leukocytes. Because thyroidal and orbital tissues are infiltrated by activated leukocytes in Graves' disease, a cross-sectional study to visualize disease activity with [111In-DTPA-D-Phe1]octreotide scintigraphy was performed. A correlation between thyroidal [111In-DTPA-D-Phe1]octreotide accumulation and free T4 (disease expression) and thyroid binding-inhibiting immunoglobulins (disease activity) is present in untreated hyperthyroid Graves' disease. There is also a correlation between orbital [111In-DTPA-D-Phe1]octreotide uptake and the clinical activity score (disease activity) and total eye score (disease expression), respectively, in Graves' orbitopathy. Visualization of thyroidal and orbital Graves' disease is feasible, but further investigation is necessary to establish the role of [111In-DTPA-D-Phe1]octreotide scintigraphy in representing disease activity and expression and in predicting therapeutical outcome.
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PMID:[111In-DTPA-D-Phe1] octreotide scintigraphy in thyroidal and orbital Graves' disease: a parameter for disease activity? 798 93

Thyroid Associated Ophthalmopathy (TAO) is an autoimmune disorder generally associated with Graves' disease (GD). The aim of our study was to evaluate the uptake of indium-111 Octreotide (111In-OCT), a somatostatin (SS) analogue able to bind specific SS receptors, at the level of the thyroid and orbits in patients with TAO. Seven patients with exophthalmos were investigated: six had GD while one was affected with a non small cell lung cancer (NSCLC). One patient with GD had undergone total thyroidectomy (TT) for a thyroid cancer. At the time of the study two patients were hyperthyroid, four were euthyroid and one was hypothyroid. 111 MBq of 111In-OCT were i.v. injected and two 30-minute scans were performed at 4 and 24 hours; 5 minute planar images were also obtained at 25, 60 and 120 minutes. A 180 degrees SPECT was carried out 5 hours after the injection in one patient. A qualitative analysis was performed, comparing these images with those obtained in 7 control patients without thyroid illness or exophthalmos. Moreover, in the TAO patients thyroid, orbit and brain counts were evaluated in comparison with background (BK) and blood activity (BA), measured at the level of the venous longitudinal sinus. In GD intense thyroid uptake was demonstrated independently of the functional state, with highest ratio compared to BK seen at 24 hours. Low uptake in the patient with NSCLC, no activity in the patient with GD that underwent TT, and slight or absent thyroid uptake in the controls were observed. Intense uptake was seen in the orbits of the patient who clinically had the most severe ophthalmopathy.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Indium-111 octreotide in Graves' disease and in the evaluation of active exophthalmos. 857 2

Thyroid associated ophthalmopathy (TAO) is a disorder involving the soft tissues and extraocular muscles of the orbit seen mainly in cases of Graves' disease. Although an immunogenic pathogenesis has been proposed, the actual mechanisms of the in vivo retrobulbar involvement are not well defined. The recent introduction of the 111In-labeled somatostatin analog, octreotide, which can bind in vivo to the cell membrane of activated lymphocytes expressing somatostatin receptors, has provided a new investigational tool for diseases with a presumed immunological background. Based on this property, octreotide scans can be expected to be positive in cases of immunological disease showing tracer accumulation within affected sites. The aim of this study was to evaluate the utility of scintigraphic imaging with octreotide of the retrobulbar space in cases of TAO, including sequential studies of patients undergoing immunosuppressive therapy. We studied a series of 51 patients who had Graves' disease with varying degrees of TAO. Nine patients had received immunosuppressive therapy. The degree of orbital inflammation was classified according to the clinical activity score of Mourits. Both planar and tomographic imaging of the orbit were carried out using 111 MBq of the 111In-labeled octreotide (OctreoScan) 2 h after tracer injection. A significant tracer accumulation in the retrobulbar space was seen in all 20 patients with a high activity score, in 8 of 16 cases with a negative score, and in 11 of 20 cases with an intermediate Mourits' score. In cases of persistent eye disease in spite of immunosuppressive therapy, the octreotide scan remained positive. Successful therapy either with prednisolone, external radiation, or i.v. immunoglobulins showed a significant diminution of tracer uptake after finishing the therapeutic regime. Three-dimensional reconstruction of the images also revealed a significant tracer accumulation in the areas of the lacrimal gland, the nasal region, and the pituitary. Controls cases (n = 30) showed no uptake in the orbital region. We conclude that 111In octreotide scintigraphy is an objective method that identifies patients with active inflammatory eye disease, i.e., having significant tracer uptake in the retrobulbar space. This uptake appears to reflect an immunological process, since immunosuppressive therapy will significantly decrease tracer accumulation.
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PMID:Evaluation of immunological mechanisms mediating thyroid-associated ophthalmopathy by radionuclide imaging using the somatostatin analog 111In-octreotide. 934 89


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