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)

Cortisol secretion in ACTH-independent macronodular adrenal hyperplasia (AIMAH) causing Cushing's syndrome can be controlled by illegitimate receptors. The aim of the present study was to characterize the molecular, immunohistochemical, and pharmacological profiles of vasopressin receptors in cells derived from three patients with AIMAH (H1-H3), in order to evaluate the role of ectopic vasopressin receptors in the physiopathology of hypercortisolism. Expression of mRNAs encoding the vasopressin receptor types (V(1a), V(1b), and V(2)) were analyzed by RT-PCR in adrenal tissues. The presence of V(1a) and V(2) receptors was studied by immunohistochemistry on adrenal sections. The pharmacological profiles of vasopressin receptors involved in the control of cortisol secretion were investigated using the V(1a) receptor antagonist SR49059 and the V(2) receptor agonist [deamino-Cys(1), Val(4), D-Arg(8)]-vasopressin on cultured cells. The V(1a) receptor protein was present and functional in H1 and H3 tissues, whereas the V(1b) receptor was not expressed in any of the tissues. RT-PCR experiments revealed that V(2) receptor mRNAs were detected in the three tissues. In contrast, immunohistochemical and cell incubation studies showed that the V(2) receptor was involved in the stimulatory effect of AVP on cortisol secretion in H1 and H2, but not in H3 cells. Taken together, these data show that expression of functional ectopic V(2) receptors and repression of eutopic V(1a) receptor can coexist in some hyperplastic corticosteroidogenic tissues. They also reveal that immunohistochemical and incubation studies are essential for the characterization of ectopic receptors actually involved in the control of cortisol secretion by AIMAHs.
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PMID:Expression of vasopressin receptors in ACTH-independent macronodular bilateral adrenal hyperplasia causing Cushing's syndrome: molecular, immunohistochemical and pharmacological correlates. 1818 Mar 12

Cushing's syndrome due to ACTH-independent macronodular adrenal hyperplasia (AIMAH) can be associated with abnormal responses of aberrantly expressed adrenocortical receptors. This study aimed to characterize in vitro the pathophysiology of hypercortisolism in a beta-blocker-sensitive Cushing's syndrome due to AIMAH. Cortisol secretion profile under aberrant receptors stimulation revealed hyperresponsiveness to salbutamol (beta2-adrenoceptor agonist), cisapride (5-HT4 receptor agonist), and vasopressin in AIMAH cultured cells, but not in normal adrenocortical cells. By RT-PCR, AIMAH tissues revealed beta2-adrenoceptor overexpression rather than ectopical expression. MC2R expression was similar in both AIMAH and normal adrenocortical tissues. Curiously, cortisol levels of AIMAH cells under basal condition were 15-fold higher than those of control cells and were not responsive to ACTH. Analysis of culture medium from AIMAH cells could detect the presence of ACTH, which was immunohistochemically confirmed. Finally, the present study of AIMAH cells has identified: a) cortisol hyperresponsiveness to catecholamines, 5-HT4 and vasopressin in vitro, in agreement with clinical screening tests; b) abnormal expression of beta2-adrenoceptors in some areas of the hyperplastic adrenal tissue; c) autocrine loop of ACTH production. Altogether, the demonstration of aberrant responses to hormonal receptors and autocrine hormone production in the same tissue supports the assumption of multiple molecular alterations in adrenal macronodular hyperplasia.
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PMID:Cellular and molecular abnormalities of a macronodular adrenal hyperplasia causing beta-blocker-sensitive Cushing's syndrome. 1820 81

Hyper-responsiveness of plasma cortisol to vasopressin has been demonstrated in ACTH-independent bilateral macronodular adrenocortical hyperplasia (AIMAH) and some adrenal adenomas with Cushing's syndrome (CS). However, the clinical significance of hyper-responsiveness of plasma cortisol to vasopressin has not been investigated systematically in adrenal nodule(s). The aim of this study was to clarify the prevalence of hyper-responsiveness of plasma cortisol to vasopressin (vasopressin responder) and their clinical characteristics in terms of hormonal secretion using vasopressin-loading test in the patients with adrenal nodule(s) except pheochromocytomas. A vasopressin-loading test was performed on 61 consecutive patients with adrenal nodules (CS: 33, aldosterone-producing adenoma: 10, non-functional tumor: 18). Vasopressin responders were observed in 36.1% of adrenal nodule(s), 42.4% of CS and 28.5% of non-CS. In responders with CS, eight patients had bilateral nodules that were diagnosed as AIMAH, and the remaining six patients had a unilateral nodule. These patients had lower plasma cortisol than non-responders at both morning (P<0.01) and midnight (P<0.05), as well as the morning following overnight dexamethasone suppression at 1mg (P<0.05) and 8mg (P<0.05). Hyper-responsiveness of the adrenal gland to vasopressin resulting in enhanced plasma cortisol was frequently observed among patients with adrenal nodule(s). The vasopressin responders among the patients with adrenal nodule(s) frequently had CS with low autonomous cortisol secretion.
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PMID:Hyper-responsiveness of adrenal gland to vasopressin resulting in enhanced plasma cortisol in patients with adrenal nodule(s). 1862 13

Vasopressin was reported to stimulate secretion of both cortisol and aldosterone through eutopic V1a receptors in adrenal gland. Recently, adrenal hyper-responsiveness of plasma cortisol to vasopressin with eutopic overexpession of V1a receptors has been reported in Cushing's syndrome, such as a majority of cases of ACTH-independent macronodular adrenal hyperplasia and some cases of Cushing's adenomas. There were a few reports regarding the aldosterone response to vasopressin in aldosterone-producing adenoma. The aim of our study was to investigate the aldosterone response to vasopressin and its pathophysiological roles in the patients with aldosterone-producing adenoma. Vasopressin-loading test was performed in 10 patients with aldosterone-producing adenoma, and in 16 patients with non-functioning adrenal tumors. The roles of the aldosterone response to vasopressin were analyzed in terms of hormonal secretion and the expression of V1a receptor mRNA on the operated adrenal gland in aldosterone-producing adenoma. We found that (1) a varying aldosterone response to vasopressin was observed, (2) absolute response of plasma aldosterone in aldosterone-producing adenoma was significantly higher than that in non-functioning tumor, (3) aldosterone response rate to vasopressin was significantly and negatively correlated with the decline rate (%) in plasma aldosterone from morning to evening in aldosterone-producing adenoma, (4) V1a receptor mRNA was expressed at various values in aldosterone-producing adenoma, and (5) surgical removal of aldosterone-producing adenoma eliminated the aldosterone response to vasopressin observed in patients with aldosterone-producing adenoma. These findings indicated that vasopressin might be involved in the coordination of aldosterone secretion through eutopic expression of V1a receptor in aldosterone-producing adenoma.
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PMID:A possible association between aldosterone response to vasopressin and circadian change of aldosterone in the patients with aldosterone-producing adenoma. 1883 94

Paraneoplastic syndromes (PNS) represent the clinical manifestation of the remote and indirect effects produced by tumor metabolites or other products. Paraneoplastic effects are not directly mediated by tumor invasion of normal tissue, or by the disruption of normal function of the involved organ, or by distant metastases. More than 260 cases of nasopharyngeal carcinoma (NPC) associated with PNS have been reported in the literature. These syndromes can be divided into six main groups: cutaneous or dermatologic, endocrine, hematologic, osteoarticular or rheumatologic, neurologic, and ocular. The most common dermatologic manifestation is dermatomyositis, while the syndrome of inappropriate secretion of antidiuretic hormone and occasionally Cushing's syndrome due to ectopic ACTH production are the endocrinologic manifestations. Tumor fever and leukemoid reaction, osteoarticular or rheumatic syndromes, including clubbing of the fingers and toes, sensory neuropathy and demyelinating motor polyneuropathy, and rarely optic neuritis represent the most prominent examples of the other groups of syndromes. PNS may occur before the NPC is manifest, or while it is in an occult stage, and thus the possibility of NPC should be considered in patients with these various disorders. While some PNS will respond to direct treatment, most often the PNS subsides in parallel to response of the NPC, and thus may be useful for monitoring tumor response or recurrence.
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PMID:Paraneoplastic syndromes in patients with nasopharyngeal cancer. 1911 98

Cushing's syndrome is a complex endocrine condition with potential serious complications if untreated or inadequately treated. Transsphenoidal surgery with resection of a pituitary adenoma is successful in 75 - 80% of patients, but approximately 20 - 25% show persistence of Cushing's, and a similar proportion may experience recurrence within 2 - 4 years post-op. When surgery fails, medical treatment can temporarily suppress excessive cortisol production and ameliorate its clinical manifestations while more definitive therapy becomes effective. We describe pharmacological approaches to the treatment of Cushing's syndrome. Drugs used to suppress cortisol secretion are mostly inhibitors of steroidogenesis. Ketoconazole, fluconazole aminoglutethimide, metyrapone, mitotane and etomidate are in that category. Ketoconazole is in current use while other drugs, although mostly available in the past, continue to have a potential role either alone or in combination. Drugs that suppress adrenocorticotropic hormone (ACTH) secretion are less popular as standard treatment and include cyproheptadine, valproic acid, cabergoline, somatostatin analogs, PPAR-gamma agonists, vasopressin antagonists. Some of these drugs have been tested in limited clinical trials but there is potential therapeutic benefit in analogs with better specificity for the class of receptors present in ACTH-secreting tumors. A third category of drugs is glucocorticoid receptor antagonists. Mifepristone is currently being tested in clinical trials in patients with persistent or recurrent Cushing's disease and in patients with metastatic adrenal cortical carcinoma or ectopic ACTH syndrome not amenable to surgery. We also review replacement therapy after surgery and non-specific drugs to treat complications in patients with severe hypercortisol. The review provides a complete survey of the drugs used in the medical treatment of Cushing's, and new advances in the development of pituitary-active drugs as well as receptor blockers of glucocorticoid action. It also provides avenues for exploration of new drugs active on somatostatin, dopamine and vasopressin receptors. There are effective pharmacological agents capable of chronically reversing biochemical and clinical manifestations of hypercortisolemia in Cushing's syndrome but new drugs are needed with action at the pituitary level.
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PMID:Drugs in the medical treatment of Cushing's syndrome. 1993 10

Hypercortisolism caused by an adrenocortical tumor (AT) results from adrenocorticotropic hormone (ACTH)-independent hypersecretion of glucocorticoids. Studies in humans demonstrate that steroidogenesis in ATs may be stimulated by ectopic or overexpressed eutopic G protein-coupled receptors. We report on a screening of 23 surgically removed, cortisol-secreting ATs for the expression of receptors for luteinizing hormone (LH), gastric-inhibitory polypeptide (GIP), and vasopressin (V(1a), V(1b), and V(2)). Normal adrenal glands served as control tissues. Abundance of mRNA for these receptors was quantified using quantitative polymerase chain reaction (QPCR), and the presence and localization of these receptors were determined by immunohistochemistry. In both normal adrenal glands and ATs, mRNA encoding for all receptors was present, although the expression abundance of the V(1b) receptor was very low. The mRNA expression abundance for GIP and V(2) receptors in ATs were significantly lower (0.03 and 0.01, respectively) than in normal adrenal glands. The zona fasciculata of normal adrenal glands stained immunonegative for the GIP receptor. In contrast, islands of GIP receptor-immunopositive cells were detected in about half of the ATs. The zona fasciculata of both normal adrenal glands and AT tissue were immunopositive for LH receptor; in ATs in a homogenous or heterogenous pattern. In normal adrenal glands, no immunolabeling for V(1b)R and V(2) receptor was present, but in ATs, V(2) receptor-immunopositive cells were detected. In conclusion, QPCR analysis did not reveal overexpression of LH, GIP, V(1a), V(1b), or V(2) receptors in the ATs. However, the ectopic expression of GIP and V(2) receptor proteins in tumorous zona fasciculata tissue may play a role in the pathogenesis of canine cortisol-secreting ATs.
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PMID:Expression of receptors for luteinizing hormone, gastric-inhibitory polypeptide, and vasopressin in normal adrenal glands and cortisol-secreting adrenocortical tumors in dogs. 2039 66

Adrenocorticotropin (ACTH) independent bilateral macronodular adrenal hyperplasia (AIMAH) is a rare cause of Cushing's syndrome, characterized by bilateral adrenal lesions and excess cortisol production despite ACTH suppression. Cortisol synthesis is produced in response to abnormal activation of G-protein-coupled receptors, such as gastric inhibitory peptide, vasopressin, beta adrenergic agonists, LH/hCG and serotonin receptors. The aim of this study was to analyze the expression of glucagon receptors in adrenal glands from an AIMAH patient. A patient with ACTH-independent Cushing's syndrome and bilateral macronodular adrenal hyperplasia was screened for altered activation of adrenal receptors by physiological (mixed meal) and pharmacological (gonadotrophin releasing hormone, ACTH and glucagon) tests. The results showed abnormally high levels of serum cortisol after stimulation with glucagon. Hypercortisolism was successfully managed with ketoconazole treatment. Interestingly, a 4-month treatment with a somatostatin analogue (octreotide) was also able to reduce cortisol secretion. Finally, Cushing's syndrome was cured after bilateral adrenalectomy. Abnormal mRNA expression for glucagon receptor in the patient's adrenal glands was observed by Real-Time PCR procedure. These results strongly suggest that the mechanism of AIMAH causing Cushing's syndrome in this case involves the illicit activation of adrenal glucagon receptors. This is the first case reported of AIMAH associated with ectopic glucagon receptors.
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PMID:Aberrant expression of glucagon receptors in adrenal glands of a patient with Cushing's syndrome and ACTH-independent macronodular adrenal hyperplasia. 2052 75

The hyper-responsiveness of plasma cortisol to vasopressin has been reported in patients with ACTH-independent bilateral macronodular adrenocortical hyperplasia (AIMAH) and in certain cases of Cushing's adenomas with overexpression of V1a receptors in the adrenal gland. We previously reported a high prevalence of the adrenal hyper-responsiveness of plasma cortisol to vasopressin (vasopressin responders) in Japanese patients with Cushing's syndrome (CS), in which vasopressin responders had low autonomous cortisol secretion and were diagnosed as having subclinical CS. In the present study, we aimed to evaluate the pathophysiological significance of vasopressin responsiveness in patients with subclinical CS in terms of hormonal secretion and metabolic abnormalities. We compared 14 vasopressin responders and 13 non-responders with subclinical CS, admitted to Chiba University Hospital between 1999 and 2007. Among these patients, the vasopressin responders were found to have lower plasma cortisol levels than non-responders at midnight (P<0.05) and in the morning following overnight dexamethasone suppression at 1 mg (P<0.05). On the other hand, they showed a significantly higher frequency of hypertensive complications than non-responders. In addition, according to 75g-OGTT the vasopressin responders had significantly higher levels of plasma insulin at 60 min than the non-responders, and their cortisol response to vasopressin had a significantly positive association with HOMA-IR (r=0.671, P<0.05). A high expression level of V1a receptor mRNAs was observed in the resected adrenal glands of vasopressin responders with AIMAH and unilateral adenomas. Though vasopressin responders with subclinical CS had lower autonomous cortisol secretion, they had a high prevalence of hypertension, in which insulin resistance was closely correlated with cortisol response to vasopressin.
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PMID:Vasopressin responders have a high prevalence of hypertension and insulin resistance in spite of a lower secretion of cortisol in subclinical Cushing's syndrome. 2147

We herein present the case of a 53-year-old patient with adrenocorticotropin-independent macronodular adrenocortical hyperplasia (AIMAH), which is a rare form of Cushing syndrome. He had hypercortisolemia and bilateral macronodular adrenal glands with a left side predominance. The administration of vasopressin significantly increased the plasma cortisol level (1.9-fold). Following left adrenalectomy, the patient's hypercortisolemia significantly improved and vasopressin responsiveness was lost, suggesting that the responsiveness originated from the resected left adrenal gland. The marked difference in vasopressin responsiveness between the adrenals corresponded with their asymmetrical size and function. Evaluating the differences in the vasopressin sensitivity may therefore be helpful for understanding the progression of AIMAH.
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PMID:A marked difference in the vasopressin responsiveness between the adrenal glands in a patient with adrenocorticotropin-independent macronodular adrenal hyperplasia. 2367 93


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