Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have examined the expression profiles of the different vasopressin receptors (V1, V2, V3) that can be expressed in the three different types of tumors associated with Cushing's syndrome. V3 (V1b) receptor cDNA was cloned from a pituitary tumor responsible for Cushing's disease. We show that it is overexpressed in these tumors and can respond to DD-AVP. High expression of the V3 receptor on highly differentiated, ACTH-secreting, bronchial carcinoid tumors explain why these non-pituitary tumors occasionally respond to vasopressin, mimicking a "pituitary-like" behavior. A retrospective analysis showed that vasopressin induced an ACTH-independent cortisol rise in 27% of the adrenocortical tumors responsible for Cushing's syndrome. V1 mRNA was detected in normal adrenal cortex and in all tumors. Adenomas had significantly higher levels than carcinomas. V1 mRNA levels were higher in responders than in non-responders. One adenoma which had a brisk cortisol response in vivo, also had in vitro cortisol responses that were inhibited by a specific V1 antagonist. In situ hybridization showed the presence of V1 mRNA in the normal human adrenal cortex where the signal predominated in the compact cells of the zona reticularis. A positive signal was also present in the tumors with high V1 mRNA levels determined by RT-PCR; its distribution pattern was heterogeneous and showed preferential association with compact cells. High-and not ectopic-expression of the V1 receptor occurs in a minority of adrenal cortical tumors which become directly responsive to vasopressin stimulation.
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PMID:Vasopressin receptors modulate the pharmacological phenotypes of Cushing's syndrome. 988 81

Recent studies from several groups have indicated that abnormal or ectopic expression and function of adrenal receptors for various hormones may regulate cortisol production in ACTH-independent hypercortisolism. Gastric inhibitory polypeptide (GIP)-dependent Cushing's syndrome has been described in patients with either unilateral adenoma or bilateral macronodular adrenal hyperplasia; this syndrome results from the large adrenal overexpression of the GIP receptor without any activating mutation. We have conducted a systematic in vivo evaluation of patients with adrenal Cushing's syndrome in order to identify the presence of abnormal hormone receptors. In macronodular adrenal hyperplasia, we have identified, in addition to GIP-dependent Cushing's syndrome, other patients in whom cortisol production was regulated abnormally by vasopressin, ss-adrenergic receptor agonists, hCG/LH, or serotonin 5HT-4 receptor agonists. In patients with unilateral adrenal adenoma, the abnormal expression or function of GIP or vasopressin receptor has been found, but the presence of ectopic or abnormal hormone receptors appears to be less prevalent than in macronodular adrenal hyperplasia. The identification of the presence of an abnormal adrenal receptor offers the possibility of a new pharmacological approach to control hypercortisolism by suppressing the endogenous ligands or by using specific antagonists for the abnormal receptors.
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PMID:The diversity of abnormal hormone receptors in adrenal Cushing's syndrome allows novel pharmacological therapies. 1100 21

Hyponatremia can result from a wide range of causes. While hyponatremia is known to occur in patients with hypopituitarism, severe hyponatremia occurring as the presenting feature of hypopituitarism is very rare. We present two cases in which severe hyponatremia developed with weakness, light-headedness and seizure. The hyponatremia in these 2 cases mimicked the laboratory diagnostic criteria of a syndrome of inappropriate secretion of antidiuretic hormone (SIADH). However, the hormone studies displayed hypopituitarism. Hyponatremia was completely corrected after administering a supplement of prednisolone and L-thyroxine. Computerized tomography of the brain revealed an adenoma of the pituitary gland. These two cases illustrate that severe hyponatremia may be the presenting feature of clinically non-functional pituitary adenoma with hypopituitarism, which should be kept in mind in the differential diagnosis of hyponatremia mimicking SIADH.
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PMID:Severe hyponatremia as the presenting feature of clinically non-functional pituitary adenoma with hypopituitarism. 1183 7

Characteristic findings of the pituitary stalk on magnetic resonance (MR) imaging, which suggest a damming-up phenomenon of neurosecretory granules, were reported. Neurosecretory granules containing vasopressin influence the signal intensity on MR T1-weighted image (T1WI). The normal posterior lobe of the pituitary gland appears as a bright signal on T1WI. The bright signal of the posterior lobe represents the normal content of neurosecretory granules and disappears in patients with central diabetes insipidus. The normal pituitary stalk appears as a low-intermediate intensity signal on sagittal and coronal T1WIs with 3 mm-slice thickness. The pituitary stalk appeared as a bright signal in 20 patients; 13 with pituitary adenoma, 4 with an intrasellar cystic lesion, one with cavernous sinus mass, and 2 with no abnormal MR findings. The pituitary stalk was not severed in any of the cases. The normal bright signal of the posterior lobe disappeared in 17 patients. No patients suffered from symptoms of central diabetes insipidus when the bright pituitary stalk appeared. It is suggested that the origin of the bright signal in the pituitary stalk is the damming up and accumulation of neurosecretory granules in the nerve fibers of the hypothalamohypophyseal tract obstructed by adenoma, postoperative scarring, cystic mass and so on. Probably, the damming-up phenomenon on MR imaging represents the functional integrity of the hypothalamo-neurohypophyseal system, and should be distinguished from an ectopic posterior lobe formation which is caused by stalk transection.
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PMID:Bright pituitary stalk on MR T1-weighted image: damming up phenomenon of the neurosecretory granules. 1208 Dec 35

Although the production of pituitary hormones by adenohypophysial tumors has been studied extensively, an examination of the immunophenotype of pituitary adenomas using a broad spectrum of antibodies has not been previously investigated. We studied 23 pituitary adenomas using a large panel of antibodies to determine if these tumors exhibited a common immunophenotype. Various neuroendocrine markers, synaptophysin, neuron-specific enolase (NSE), and the intermediate filament protein, low-mol-wt keratin were expressed in most examples. There was, however, differential expression of chromogranin A in that few prolactin (PRL) and adenocorticotrophic hormone (ACTH) adenomas stained positively, whereas all other adenoma subtypes were reactive. The ACTH adenomas had a unique profile with positive staining for galanin, neurophysiri, vasopressin, and ubiquitin. These results indicate that (1) pituitary adenomas do not express a single "generic" immunophenotype; (2) synaptophysin is the most reliable and best broad spectrum marker for pituitary adenomas; (3) the neuroendocrine granule marker chromogranin A is useful in the identification of null cell adenoma, a tumor that usually does not stain for anterior pituitary tumors; and (4) among pituitary tumors, ACTH adenomas have a unique immunoprofile.
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PMID:The Immunophenotype of Pituitary Adenomas. 1211 42

In dexamethasone-suppressed healthy volunteers, the serotonin4 (5-HT4) receptor agonist cisapride and lysine vasopressin [LVP, an analog of arginine vasopressin (AVP)] have no influence on plasma cortisol levels (PCL). In contrast, cisapride and AVP have been shown to stimulate cortisol secretion in patients with adrenal tumor or bilateral adrenal hyperplasia and Cushing's syndrome. In this report, we describe a case of adrenocortical adenoma causing subclinical Cushing's syndrome. Cisapride and terlipressin, a precursor of LVP, both induced an increase in PCL reaching +88% and +100%, respectively, without any significant variation of plasma ACTH levels. In vitro experiments were conducted to investigate the effects of 5-HT and AVP on cortisol production from cultured tumor cells and normal adrenocortical cells. 5-HT and AVP both induced a dose-dependent increase in cortisol production from cultured tumor cells. Comparison of the data obtained with tumor and normal cells, respectively, showed that 5-HT was more efficient to stimulate steroidogenesis in adenomatous than normal cells. Concurrently, the efficacy and potency of AVP were both higher in tumor than normal cells. Collectively, these results show that the abnormal in vivo responses of the adrenocortical adenoma to cisapride and LVP could be ascribed to an increased sensitivity of the tumor tissue to 5-HT and AVP. The data also suggest that the adrenocortical tumor overexpressed eutopic 5-HT4 and V1 receptors.
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PMID:Effects of serotonin and vasopressin on cortisol production from an adrenocortical tumor causing subclinical Cushing's syndrome. 1253 Jun 99

Desmopressin (DDAVP), an arginine vasopressin analogue, markedly stimulates ACTH secretion in patients with Cushing's disease, in contrast to its minimal effect in normal subjects. However, little is known about the mechanisms underlying this action and it appeared to be of interest to evaluate the effect of DDAVP on ACTH-secreting pituitary adenomas in vitro, in comparison with its effect in the same patients in vivo. Pituitary adenomas from 14 patients with Cushing's disease were incubated with DDAVP, corticotrophin-releasing hormone (CRH) and DDAVP together with vasopressin receptor antagonists or CRH. Incubation with DDAVP induced a modest dose-dependent increase in ACTH concentrations which appeared maximal at 10 nM. CRH stimulated ACTH to a greater extent compared with DDAVP and potentiated the effect of DDAVP alone. The DDAVP-induced ACTH increase appeared blunted by vasopressin V(2) and V(3) receptor antagonists. V(3) receptor gene expression was detected by RT-PCR in all adenoma samples except for two which were not responsive to DDAVP in vitro but responsive to the peptide in vivo. Surprisingly, no difference in the in vitro ACTH secretory response was observed between in vivo DDAVP-responsive (ACTH peak>150% baseline) and -unresponsive (ACTH peak<120% baseline) patients, suggesting that the pituitary adenoma is not the sole mediator of the ACTH-releasing effect of DDAVP. In conclusion, the marked stimulatory effect of DDAVP observed in patients with Cushing's disease appears to be mainly dependent on an extrapituitary action, possibly the inhibition of a corticotrophin release-inhibitory factor.
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PMID:Corticotrophin-releasing activity of desmopressin in Cushing's disease: lack of correlation between in vivo and in vitro responsiveness. 1277 17

Chester-Erdheim disease is a rare non-Langerhans histiocytosis, affecting within the CNS mainly the neurohypophyseal unit, the retrobulbar space and the parenchyma of cerebellum, cerebrum and brainstem. Here we present a case of a 55-year-old woman who developed an exophthalmus, edema and dyspnea, finally leading to death 4 months post admission to the hospital. A cMRI showed a retrobulbar fibrosis, a tumor in the sella turcica, and further tumor formation expanding from the pons to the spinal cord, but without involvement of the dural sheet. Autopsy revealed multiple tumors attached to the pituitary gland, the tentorium, and the brainstem as well as a diffuse thickening of the dura. Histologically, the tumor tissue consisted of densely packed lipid-laden foamy macrophages positive for CD68 and intervening fibrillary cords. Interestingly, tumor cells did not infiltrate/affect the parenchyma but showed a strictly extracerebral/ subdural location. In addition, sections of the pituitary tumor revealed a chromophobe giant adenoma of the pituitary gland. As to our knowledge this is the first detailed description of an exceptional case of intracranial CED presenting with strictly extracerebral/subdural tumor masses accompanied by a giant adenoma of the pituitary gland.
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PMID:Extracerebral subdural manifestation of Chester-Erdheim disease associated with a giant adenoma of the pituitary. 1453 50

We demonstrated severe hyponatremia in a 68 year-old man who had pituitary tumor. He had poor appetite and was disoriented. Tests revealed hyponatremia of 110 mmol/l, and he was admitted to Jichi Medical School Omiya Medical Center to undergo further tests. Physical findings revealed disturbance of consciousness with Japan Coma Scale I-2. There was neither dehydration nor edema. Laboratory data showed a serum sodium level of 112 mmol/l; plasma osmolality, 219 mmol/kg; and urinary osmolality, 555 mmol/kg. Plasma arginine vasopressin (AVP) level was 1.6 pmol/l despite the marked hypoosmolality. Anterior pituitary function was normal. Brain magnetic resonance imaging showed a pituitary tumor of 20 x 18 x 20 mm in size, which pushed the pituitary stalk upward. After the adenomectomy, serum sodium level was kept normal without any treatment. Histology showed basophilic adenoma. These findings indicate that local pituitary tumor may cause exaggerated secretion of AVP, resulting in the syndrome of inappropriate secretion of antidiuretic hormone (SIADH).
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PMID:SIADH closely associated with non-functioning pituitary adenoma. 1535

Two patients with incidentally discovered adrenocortical adenomas underwent a series of pharmacological and physiological tests after pretreatment with dexamethasone. Illicit plasma cortisol responses to the serotonin (5-HT)4 receptor agonist cisapride were observed in the two patients. Significant increases in plasma cortisol levels were also noticed after glucagon and combined TRH/GnRH/GHRH stimulation tests in patient 1 and after administration of the lysine vasopressin precursor terlipressin in patient 2. After adrenalectomy, in vitro studies were conducted to investigate the cortisol responses of cultured tumor cells to serotonergic ligands and peptide hormones. In the two cases, 5-HT stimulated cortisol secretion from tumor cells with increased efficacy and/or potency to activate steroidogenesis by comparison with normal adrenocortical cells. The corticotropic effect of 5-HT was inhibited by the specific 5-HT4 receptor antagonist GR 113808 and more potently by methiothepin, a nonspecific serotonergic antagonist having no affinity for the 5-HT4 receptor. These results show that the hypersensitivity of the tumors to 5-HT was related to tissue expression of an ectopic serotonergic receptor in addition to the eutopic 5-HT4 receptor. In the two adenoma tissues, immunohistochemical studies revealed the presence of 5-HT-like immunoreactivity within clusters of steroidogenic cells, suggesting that 5-HT acted through an autocrine/paracrine mechanism to stimulate steroidogenesis. Glucagon and GnRH but not TRH, GHRH, and human chorionic gonadotropin stimulated cortisol secretion from tumor 1 cells. In conclusion, this study provides the first observation of adrenocortical cortisol-producing adenomas hypersensitive in vivo and in vitro to serotonergic agonists. Our results also show that cortisol-producing adenomas can express simultaneously several illegitimate receptors.
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PMID:Abnormal sensitivity of cortisol-producing adrenocortical adenomas to serotonin: in vivo and in vitro studies. 1613 68


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