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)

It may sometimes be difficult to distinguish Cushing's disease from ectopic ACTH syndrome. A case is described here of a patient with a Cushing's syndrome and diagnostic difficulties. Initial features were consistent with a Cushing's disease (in particular metopirone test was positive). Because of relapse of hypercortisolism after mitotane therapy, total adrenalectomy was performed. Thereafter features occurred that evoked Nelson's syndrome, including high plasma ACTH levels and a pituitary mass syndrome. Pituitary reserve testings by vasopressin or corticotropin-releasing factor were positive, although inconstantly, in that plasma ACTH increased. A lung tumor was discovered about 20 yr after the first clinical signs of hypercortisolism. Its removal led to the discovery of a bronchial carcinoid tumor and was followed by normalization of plasma ACTH levels. An analysis of proopiomelanocortin-related peptides was performed postoperatively on the blood drawn before and after the tumor resection and on the tumor; the results of this study would have been contributive to the diagnosis of occult ectopic ACTH tumor. In conclusion this case demonstrates the limitations of the conventional procedures in the diagnosis of the ectopic ACTH syndrome. At contrast the newer biochemical procedures may be very useful in determining the type of hypercortisolism.
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PMID:A case of pseudo-Nelson's syndrome: cure of ACTH hypersecretion by removal of a bronchial carcinoid tumor responsible for Cushing's syndrome. 217 23

Neurohypophysis is composed of nerve fibers and has an intimate morphologic and functional contact with the hypothalamus. Pathology of the posterior lobe of the pituitary gland may develop several clinical features such as diabetes insipidus, which is caused by infections, vascular events, surgical complications and benign and malignant tumors as well as metastasis. Inappropriate secretion of vasopressin (Schwartzbartter syndrome) is due to excessive vasopressin release from the posterior pituitary or the ectopic production by various tumors, mainly carcinoid of the lung.
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PMID:Pathology of the neurohypophysis. 307 May 5

Biochemical evidence suggests that ectopic hormone production is much more common than suspected clinically. The majority of lung carcinomas of oat cell or carcinoid type appear to synthesise ACTH and related peptides, calcitonin and less frequently, chorionic gonadotrophin and vasopressin. The primary amino acid sequences of ectopic hormones closely resemble their normal counterparts but ectopic hormone producing tumours contain greater proportions of high molecular weight, subunit and fragment forms than the normal gland of origin. Assays for ectopic hormones are clinically useful in diagnosis, tumour localisation, and monitoring patients with ectopic hormonal syndromes. Currently the clinical value of hormone assays in the routine management of common forms of malignancy in the absence of overt ectopic hormonal syndromes is unproven. However, better characterisation of hormonal forms relatively specific for neoplasia together with improved assay specificity and sensitivity may enhance the clinical value of ectopic hormones as tumour markers, particularly in malignancies which are commonly associated with ectopic hormone production (e.g. lung cancer).
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PMID:Ectopic hormones--biochemical aspects. 625 53

Opiate receptors in the central nervous system may be classified according to pharmacological, behavioural, or binding studies. Classical mu-receptors probably have beta-endorphin as an endogenous ligand, and seem to be involved in the modulation of pain perception, low-frequency acupuncture analgesia, and the stimulation of prolactin, growth hormone and thyroid-stimulating hormone release. Met-enkephalin is likely to be an endogenous ligand for the delta-receptors, which predominate in the basal ganglia and limbic systems; such receptors may tonically inhibit the release of corticotrophin-releasing factor. It has been suggested that the newly-described kappa-receptors may inhibit the release of vasopressin and gonadotrophin-releasing factor; dynorphin may be their endogenous ligand. Endogenous opiates controlling cardiovascular and respiratory reflexes are likely to activate mu-receptors, while high-frequency acupuncture may alleviate the symptoms of opiate withdrawal by allowing an increase in Met-enkephalin to activate delta-receptors. In the periphery, beta-endorphin is concentrated in the corticotrophs of the anterior pituitary, and is cosecreted with ACTH and related peptides. Circulating Met-enkephalin originates in the gut, sympathetic nervous system and adrenal medulla. Met-enkephalin may also be extracted from carcinoid tumours and phaeochromocytomas. Elevations in circulating Met-enkephalin may occur in certain disease states with cardiovascular and psychiatric manifestations. However, manipulation of endogenous or exogenous opiates has as yet no certain place in any clinical situation.
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PMID:Opiate receptors: enkephalins and endorphins. 630 48

An autopsy case of a 67-year-old Japanese male is presented. He had been suffering from carcinoid syndrome for 5 years and showed a typical picture of carcinoid heart disease. In Japan, carcinoid heart disease is rare and we can find only four reported cases (33% of reported carcinoid syndrome). The patient had high urinary secretion of 5-HIAA and high serum serotonin, and finally he died of heart failure and bronchopneumonia. The primary site of this carcinoid tumor was of the bronchus of the right B10c , and it had large hepatic metastases. Electronmicroscopically, the tumor cells had secretory granules measuring 1500-3500 A in diameter. Immunohistochemically, the tumor cells were markedly positive for human chorionic gonadotropin (hCG) and antidiuretic hormone (ADH) and positive for serotonin, in both the primary site and hepatic metastases. Characteristic fibrous plaques were detected in the right atrium, tricuspid valve, right ventricle, and left atrium. Electron-microscopically, the fibrous plaques consisted of smooth muscle cells and myofibroblasts surrounded by basement membrane-like material. The abundant matrix of the fibrous plaques contained acid mucopolysaccharide, microfibrils and collagen fibers. The same fibrous plaques were also found in hepatic veins. Furthermore, retroperitoneal fibrosis was present, which showed proliferation of myofibroblasts, fibroblasts and immature mesenchymal cells.
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PMID:Cardiovascular lesion of carcinoid syndrome. An autopsy case of bronchial carcinoid. 673 Sep 65

Simultaneous bilateral inferior petrosal sinus (IPS) sampling has been repeatedly proposed to be a highly specific approach for the diagnosis of Cushing's disease and 100% sensitivity in detecting autonomous pituitary ACTH secretion by an adenoma has been reported in a large series. We now report on a patient suffering from ACTH-dependent Cushing's syndrome in whom repeated bilateral IPS sampling failed to detect a central/peripheral gradient diagnostic for autonomous pituitary ACTH secretion during initial evaluation. Applying lysine vasopressin as the corticotroph secretatogue, the maximum central/peripheral gradient was 1.0 before and 1.1 following stimulation. Moreover, results of high dose dexamethasone and corticotrophin releasing hormone administration suggested ectopic ACTH secretion. Since thorough diagnostic procedures failed to localise a suspected carcinoid tumour, occult ectopic Cushing's syndrome was diagnosed. Eight years later, a pituitary macroadenoma was detected by magnetic resonance imaging (MRI), IPS catheterisation then revealed a maximal central/ peripheral gradient of 9.3 before and 20.4 after the intravenous administration of lysine vasopressin. Resected tumour tissue was classified as a typical densely granulated ACTH cell adenoma. We conclude that repeated MRI scans should be included in the follow-up of patients with a diagnosis of occult ectopic Cushing's syndrome to avoid the risk of overlooking 'occult eutopic Cushing's syndrome'.
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PMID:Occult eutopic Cushing's syndrome--failure of simultaneous bilateral petrosal sinus sampling to diagnose pituitary-dependent Cushing's syndrome. 924 5

A desmopressin-induced ACTH increase has been recently suggested to be specific for pituitary-dependent Cushing's disease. We present the case of a 47-year-old woman with Cushing's syndrome due to ectopic ACTH production by a bronchial carcinoid. While CRH failed to induce an ACTH or cortisol response, intravenous administration of desmopressin led to a 47% increase in serum ACTH and a 42% increase in serum cortisol concentration. After surgical removal of the tumour, the desmopressin response became negative. In vitro, ACTH production by tumour cells obtained at surgery was also stimulated by desmopressin but not by CRH. Additional receptor mRNA expression studies using RT-PCR revealed expression of both V2 and V3 vasopressin receptor subtypes in the carcinoid tumour at a level comparable to that recently described in pituitary corticotroph adenomas. This case illustrates that ACTH stimulation by desmopressin is not specific for pituitary-dependent Cushing's syndrome as vasopressin receptor subtypes known to interact with desmopressin may also be found in ectopic tumours producing ACTH.
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PMID:Ectopic ACTH production by a bronchial carcinoid tumour responsive to desmopressin in vivo and in vitro. 942 3

In the etiological diagnosis of ACTH-dependent Cushing's syndrome, it may be difficult to distinguish pituitary disease from ectopic ACTH production, specially when this is due to a benign neuroendocrine tumor. We describe a patient with partial dexamethasone suppression consistent with Cushing's disease, an absent response to CRH suggesting ectopic ACTH production and an atypical, apparent circadian rhythm. Bilateral cavernous sinus catheterization suggested a nonpituitary source of ACTH and, in the search of an ectopic tumor, somatostatin receptor scintigraphy, abdominal CT scan, and duodenopancreatic endoscopic echography were performed and failed to reveal any abnormality. Thoracic CT scan disclosed a tiny right lung nodule that showed a definite tracer uptake on MIBG scintigraphy. After resection, the nodule proved to be an 8-mm typical pulmonary carcinoid, with positive immunostaining for the classical neuroendocrine markers and for ACTH, and showing tissue expression of the POMC gene. However, the CRH receptor gene was not expressed, explaining the absent CRH response in vivo, whereas the V3 vasopressin receptor gene was expressed in the tumor tissue. The latter feature appears to be characteristic of benign carcinoids and may contribute to explaining the CRH-independent circadian rhythm observed in this case.
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PMID:Ectopic ACTH Cushing's syndrome: V3 vasopressin receptor but not CRH receptor gene expression in a pulmonary carcinoid tumor. 983 45

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

A 56-yr-old woman was referred with a diagnosis of Cushing's disease. Hypertension and severe hypokalemia were present and high urinary free cortisol/cortisone ratio was detected, raising a suspicion of an ectopic ACTH syndrome. Inferior petrosal sinus sampling, thoracic computed tomography, and octreotide scans were negative. Remission and relapse periods lasting 3-4 months were observed during the 3.5 yr of follow-up. Finally a thoracic computed tomography scan showed a basal paracardic nodule in the left lung. After surgery, a well-differentiated neuroendocrine tumor (typical bronchial carcinoid) was diagnosed, staining positively for ACTH. RT-PCR revealed expression of proopiomelanocortin, CRH receptor, and V3 vasopressin receptor. Somatostatin receptor type 1, 2, 3, and 5 mRNA was detected only in tumoral tissue. Interestingly, we observed the simultaneous presence of ghrelin and both GH secretagogue (GHS) receptors (1a and 1b) mRNA in tumoral tissue but not in the normal lung. This finding correlates with the in vivo ACTH hyperresponsiveness to hexarelin (a GHS). This is the first report of a cyclical ectopic ACTH-secreting tumor with an in vivo ACTH response to hexarelin coupled with the tumoral expression of ghrelin and GHS receptors. This finding might imply an autocrine/paracrine modulatory effect of ghrelin in bronchial ACTH-secreting tumors.
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PMID:Cyclical Cushing's syndrome in a patient with a bronchial neuroendocrine tumor (typical carcinoid) expressing ghrelin and growth hormone secretagogue receptors. 1467 Nov 77


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