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)

The aim of our study was to investigate the effect of hexarelin, a novel GH-releasing peptide-6 analog, and GH-releasing hormone (GHRH) (alone or in combination) on GH secretion in adult patients with increased somatostatin tone due to chronic glucocorticoid excess. We studied seven adult patients undergoing long-term (no less than 6 months) immunosuppressive glucocorticoid treatment for non-endocrine diseases (six females and one male, age range 42-68 years) and one subject (female, age 31 years) with endogenous hypercortisolism due to adrenal adenoma. Six normal subjects (four females and two males) matched for sex and age with the patients and not undergoing any therapy served as controls. All the subjects underwent the following three tests in random order: (1) human GHRH (1-29)NH2 (100 micrograms in 1 ml saline) injected as an i.v. bolus at 0 min, (2) hexarelin (100 micrograms in 1 ml saline) injected as an i.v. bolus at 0 min and (3) hexarelin (100 micrograms in 1 ml of saline) plus GHRH (100 micrograms in 1 ml saline) injected as an i.v. bolus at 0 min. After GHRH alone the patients with glucocorticoid excess showed a blunted GH response as compared with normal subjects (median delta GH: 0.9, range 0-5.6 micrograms/l vs 7:1, range 0.3-14.9 micrograms/l). No significant differences were observed in the steroid-treated group with respect to normal subjects after hexarelin alone (median delta GH: 15.5, range 1.9-45.2 micrograms/l vs 17.9, range 5.5-53.9 micrograms/l).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Comparison of the effects of growth hormone-releasing hormone and hexarelin, a novel growth hormone-releasing peptide-6 analog, on growth hormone secretion in humans with or without glucocorticoid excess. 756 33

Spontaneous and stimulated GH secretion is blunted in hypercortisolemic states due to increased hypothalamic somatostatinergic tone. However, no data are available on the characteristics of GH secretion in patients with incidentally discovered adrenal adenomas. They represent an interesting model for studying GH secretion, as a slight degree of cortisol excess may frequently be observed in such patients who do not present with any clear Cushingoid sign. In the present study, 10 patients (3 men and 7 women, aged 48-63 yr) with an adrenal mass discovered serendipitously underwent, on separate occasions, a GHRH injection alone or combined with an infusion of the functional somatostatin antagonist, arginine. Thirteen age-matched healthy volunteers served as controls. Briefly, arginine (30 g) was infused from -30 to 0 min, and GHRH (100 microg) was injected as a bolus at 0 min, with measurement of serum GH [immunoradiometric assay (IRMA)] every 15 min for 150 min. Plasma IGF-I (RIA after acid-ethanol extraction) was measured in a morning sample. The diagnosis of cortical adenoma was based on computed tomography features and pattern of uptake on adrenal scintigraphy. Patients with obesity and/or diabetes were excluded. The study design included also an endocrine work-up aimed to study the hypothalamic-pituitary-adrenal axis [urinary free cortisol (UFC) excretion, serum cortisol at 0800 h, plasma ACTH at 0800 h, morning cortisol after overnight 1 mg dexamethasone]. Five of 10 patients showed abnormalities of the hypothalamic-pituitary-adrenal axis, including borderline or increased UFC excretion in 4 of them accompanied by blunted ACTH in 2 cases and failure of cortisol to suppress after dexamethasone in 1; the fifth patient displayed low ACTH and resistance to dexamethasone suppression. However, all patients had a unilateral uptake of the tracer on the side of the mass with suppression of the contralateral normal adrenal gland. As a group, the patients displayed greater UFC excretion and lower ACTH concentrations than the controls. GH release after GHRH treatment was blunted in patients bearing adrenal incidentaloma compared with controls (GH peak, 5.7 +/- 5.2 vs. 18.0 +/- 7.0 microg/L; P < 0.0001), whereas GHRH plus arginine was able to elicit a comparable response in the 2 groups (GH peak, 33.5 +/- 20.3 vs. 33.7 +/- 17.5 microg/L; P = NS). The ratio between GH peaks after GHRH plus arginine and after GHRH plus saline was significantly greater in patients than in controls (751 +/- 531% vs. 81 +/- 45%; P = 0.0001). Similar data were obtained when comparing GH area under the curve after GHRH plus saline or GHRH plus arginine between the 2 groups. In summary, the present data suggest that in patients with incidental adrenal adenomas the GH response to GHRH is blunted due to increased somatostatinergic tone, as it can be restored to normal by pretreatment with the functional somatostatin antagonist arginine. The blunted GH release to GHRH may be an early and long lasting sign of autonomous cortisol secretion by the adrenal adenoma.
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PMID:Growth hormone (GH) responses to GH-releasing hormone alone or combined with arginine in patients with adrenal incidentaloma: evidence for enhanced somatostatinergic tone. 1072 81

Dopamine (DA) is a catecholamine with a wide range of functions and whose five subtype receptors are found in different organs where they exert a mainly inhibitory action. Since this action may also appear in a number of secretory tumors in various locations, DA agonists have elicited some interest as a medical treatment for hypercorticism. Non-iatrogenic Cushing's syndromes are due in 70% of the cases to a pituitary adrenocorticotropic hormone (ACTH)-producing adenoma, and, less frequently, to an adrenal adenoma or an ectopic ACTH secretion by a neuroendocrine tumor. First-line treatment in Cushing's syndrome consists of the surgical removal of the secreting tumor. However, surgery may not achieve a complete cure in a number of cases, hence emphasizing the potential benefit of a medical complementary treatment, which could also benefit patients as an alternative approach, either when waiting for, or when the patient is not eligible for surgery. Studies of corticotropic adenomas have shown that 80% of these tumors express D2 receptors. Clinical trials of DA agonists in Cushing's disease have shown an inhibitory effect of these drugs with an inhibition of ACTH secretion and/or a decrease of tumor size. There are only a few cases of documented use of DA agonists in ectopic ACTH secretion, but when the tumor expresses DA receptors, DA agonists may represent a useful complementary treatment. DA receptors are also expressed in normal and tumoral adrenals, suggesting a potential use of DA agonists in Cushing's syndrome secondary to adrenal tumors. However, clinical data regarding this specific situation are very scarce, maybe due to the relatively high rate of surgical cure of adrenal adenomas. In conclusion, DA agonists represent a potential preparatory or complementary treatment for endogenous Cushing's syndrome, especially in Cushing's disease. These compounds may be underused as suggested by the scarce number of publication and case reports in the literature. In the future, association of these drugs with somatostatin analogs may also prove beneficial.
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PMID:Medical treatment in Cushing's syndrome: dopamine agonists and cabergoline. 2082 31

Adrenocortical adenomas display highly variable expressions of somatostatin receptor (SSTR) subtypes, whose expression is mandatory (although not always sufficient) to achieve the positive effects of somatostatin (SST) analog therapy. Immunohistochemistry (IHC) is the main method used to investigate receptor protein expression. The molecular biology method - polymerase chain reaction (PCR) - is also often used to investigate receptor expression. Nevertheless, the expression of receptor mRNA and the respective receptor protein is not always synchronized. The aim of this study was to investigate SSTR expression by IHC in adrenal adenomas, to compare the results to data obtained by real-time PCR and to determine whether hormonally functioning and non-functioning adenomas differ in this respect. Adrenocortical adenomas were removed surgically from 13 females and 2 males. The tissues were obtained from 9 non-functioning and 6 functioning adenomas. The intensity of IHC reaction was scored semiquantitatively by two independent observers. Real-time PCR was performed using pairs of primers in a reaction amplified along a gradient of temperatures. Amplified DNA was measured by monitoring SYBR-Green fluorescence. In non-functioning tumors, compatibility between IHC and PCR results was observed for SSTR 1 and 2 in 62.5% of the samples. Fifty percent of patients demonstrated compatibility for SSTR 4 and 5 and 37.5% for SSTR 3. In hormonally active adenomas, total compatibility of both methods was noted for SSTR 2 (100%). The compatibility obtained for SSTR 5 was 66.6%. We conclude that receptor gene and respective receptor protein expression are not always synchronized. Messenger RNA detection alone is not sufficient to predict the presence of the receptor protein acting as a target for SST and its analogs.
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PMID:Differential expression of somatostatin receptor subtype-related genes and proteins in non-functioning and functioning adrenal cortex adenomas. 2172 Jul 16

We herein describe the case of a 47-year-old woman with pre-clinical Cushing's syndrome caused by a left adrenal adenoma, which was diagnosed 6 years after trans-sphenoidal selective removal of a pituitary adenoma for acromegaly at age 35. The patient was started on bromocriptine and then somatostatin analogues after the surgery; however, since her serum insulin-like growth factor-1 (IGF-1) values remained above the age-adjusted normal range, the treatment for acromegaly was switched from somatostatin analogues to pegvisomant (10 mg daily), before a left laparoscopic adrenalectomy. After the subsequent adrenalectomy, the dose of pegvisomant could be reduced gradually to once every 4 days without any increase in the serum IGF-1 values. This is the first report describing the need for a different dose of pegvisomant for the treatment of acromegaly before and after adrenalectomy for pre-clinical Cushing's syndrome.
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PMID:A decrease in the dose of pegvisomant was needed for the treatment of acromegaly after adrenalectomy in a patient with coexisting preclinical Cushing's syndrome. 2192 82