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)

Vasopressin (AVP) is a cyclic nonapeptide hormone that exhibits many physiological effects including free water reabsorption, vasoconstriction, cellular proliferation and adrenocorticotrophic hormone (ACTH) secretion. In a healthy organism, AVP plays an important role in the homeostasis of fluid osmolality and volume status. However, in several diseases or conditions such as the syndrome of inappropriate secretion of AVP (SIADH), congestive heart failure, arterial hypertension, liver cirrhosis, nephrotic syndrome, dysmenorrhoea and ocular hypertension, AVP may play an important role in their pathophysiology. Recently, orally-active non-peptide AVP receptor antagonists were developed by random screening of chemical entities and optimisation of lead compounds. These include agents specific for the V(1)-vascular and V(2)-renal AVP receptor subtypes. Dual V(1)/V(2) AVP receptor antagonists are also being studied. Some of these non-peptide receptor antagonists have been studied extensively, while others are currently under investigation. Potential therapeutic indications for AVP receptor antagonists comprise: 1) The blockade of V(1)-vascular AVP receptors in arterial hypertension, congestive heart failure, Raynaud's syndrome, peripheral vascular disease and dysmenorrhea. 2) The blockade of V(2)-renal AVP receptors in the syndrome of inappropriate secretion of vasopressin, congestive hart failure, liver cirrhosis, nephrotic syndrome and any state of excessive retention of free water and subsequent dilutional hyponatraemia. 3) The blockade of V(3)-pituitary AVP receptors in ACTH-secreting tumours. This review examines the pharmacology of orally-active non-peptide AVP receptor antagonists and their clinical applications.
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PMID:Development and therapeutic indications of orally-active non-peptide vasopressin receptor antagonists. 1132 60

Lixivaptan is a non-peptide, orally-active vasopressin antagonist under development by American Home Products for the potential treatment of hyponatremia associated with diseases such as heart failure, liver cirrhosis and nephrotic syndrome. By 1997, it was in phase II trials in the US and elsewhere for hyponatremia [2424051. It selectively prevents vasopressin-dependent water resorption, increasing water excretion with low electrolyte loss [266993] and is selective towards the human V2 versus V1 receptors [295987].
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PMID:Lixivaptan (American Home Products). 1156 11

Renal sodium retention is responsible for ascites and edema in nephrotic syndrome. In puromycin aminonucleoside (PAN)-induced nephrosis, sodium retention originates in part from the collecting duct, and it is associated with increased Na,K-ATPase activity in the cortical collecting duct (CCD). The aims of this study were to evaluate whether the outer medullary collecting duct (OMCD) also participates to sodium retention and to determine the mechanisms responsible for stimulation of Na,K-ATPase in CCD. PAN nephrosis increased Na,K-ATPase activity in the CCD but not in OMCD. The two-fold increase of Na,K-ATPase activity in CCD was associated with two-fold increases in the number of alpha and beta Na,K-ATPase subunits mRNA determined by quantitative RT-PCR and of the total amount of Na,K-ATPase alpha subunits estimated by Western blotting. PAN nephrosis also increased two-fold the amount of Na,K-ATPase alpha subunit at the basolateral membrane of CCD principal cells, as determined by Western blotting after biotinylation and streptavidin precipitation and by immunofluorescence. The intracellular pool of latent Na,K-ATPase units also increased in size and was no longer recruitable by vasopressin and cAMP. This unresponsiveness of the intracellular pool of Na,K-ATPase to vasopressin was not the result of any alteration of the molecular and functional expression of the vasopressin V(2) receptor/adenylyl cyclase (AC) complex. It is concluded that PAN nephrosis (1) does not alter sodium reabsorption in OMCD, (2) is associated with increased synthesis and membrane expression of Na,K-ATPase in the CCD, and (3) alters the normal trafficking of intracellular Na,K-ATPase units to the basolateral membrane.
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PMID:Increased synthesis and avp unresponsiveness of Na,K-ATPase in collecting duct from nephrotic rats. 1167

Nephrotic edema are the clinical feature of isolated interstitial expansion. Expanded interstitial compartment compensates sodium accumulation in the extracellular volume due to inappropriate renal sodium retention. Renal sodium retention is brought about by an activation of the molecular structures responsible for the reabsorption of sodium along the cortical collecting duct: amiloride-sensitive epithelial sodium channel at the apical face and sodium pump at the basolateral face of the principal cell. This activation is independent of aldosterone and vasopressin. The asymmetry of expansion between interstitium and plasma compartments is due to impaired Starling forces and increased fluid transfer through the capillary wall. The lack of significant changes in transcapillary oncotic and hydrostatic gradients suggests that increased hydraulic conductivity due to transconformation of endothelial intercellular junctions drives the leakage of fluid into the interstitium and allows to understand the mobility of nephrotic edema. Consistently with the site of renal sodium retention and the activation of the epithelial sodium channel, the association of amiloride and furosemide is efficient to increase urinary sodium excretion, to reverse sodium balance and to remove edema from patients with nephrotic syndrome.
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PMID:[Molecular mechanism of edema formation in nephrotic syndrome]. 1535 Oct

The underfill and overflow hypotheses are usually held as mutually exclusive mechanisms for explaining sodium/water retention in nephrotic syndrome, but neither of them is entirely convincing. In this paper, we will briefly summarize the experimental and clinical evidence in favor of and against each hypothesis. Based on our personal observations, we propose a unifying hypothesis in which underfill and overflow are subsequent stages of the disease. In the transition, a central role is played by vasopressin, which is secreted in the two phases, respectively, by a volume and an osmotic stimulus; therefore, persistent sodium/water retention is maintained through the vascular and tubular effects of this peptide. In addition, we propose that vasodilation and sodium/water excretion could ensue when both stimuli for vasopressin release fade away, leading to the resolution of the syndrome.
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PMID:Central role of vasopressin in sodium/water retention in hypo- and hypervolemic nephrotic patients: a unifying hypothesis. 1559 31

Vasopressin (AVP) and oxytocin (OT) are cyclic nonapeptides whose actions are mediated by the stimulation of specific G-protein-coupled receptors (GPCRs) currently classified into V(1)-vascular (V(1)R), V(2)-renal (V(2)R) and V(3)-pituitary (V(3)R) AVP receptors and OT receptors (OTR). The signal transduction pathways coupled to the different subtypes of AVP/OT receptors are reviewed. The recent cloning of the different members of the AVP/OT family of receptors now allows the extensive characterisation of the molecular determinants involved in agonist and antagonist binding, as well as signal transduction coupling. Potential therapeutic uses of AVP receptor antagonists include: the blockade of V(1)-vascular AVP receptors in arterial hypertension, congestive heart failure (CHF) and peripheral vascular diseases; the blockade of V(2)-renal AVP receptors in the syndrome of inappropriate vasopressin secretion, CHF, liver cirrhosis, nephrotic syndrome and any state of excessive retention of free water and subsequent hyponatraemia; the blockade of V(3)-pituitary AVP receptors in adrenocorticotropin (ACTH)-secreting tumours. The pharmacological and clinical profile of orally-active non-peptide AVP receptor antagonists is reviewed.
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PMID:Development and therapeutic indications of orally-active non-peptide vasopressin receptor antagonists. 1599 64

Volume retention in heart failure, nephrotic syndrome, and liver cirrhosis reflects pathological changes in homeostatic mechanisms that regulate the extracellular volume (sympathetic activity, renin-angiotensin-aldosterone system [RAAS], natriuretic peptides) and plasma osmolality (antidiuretic hormone [ADH]). In heart failure and liver cirrhosis, these changes are induced by a reduction of the effective circulating volume, which is the part of the extracellular fluid that is within the arterial system and effectively perfusing the tissues. This reduction in the effective circulating volume is caused by reduced cardiac output (heart failure), or by splanchnic vasodilatation with arterial underfilling (liver cirrhosis). In both cases, baroreceptors in both the carotid sinuses and in the glomerular afferent arterioles upregulate RAAS- and sympathetic activity, resulting in systemic vasoconstriction and renal sodium (and volume) retention. More severe reductions in the effective circulating volume may additionally stimulate ADH release, thus increasing the reabsorption of free water with subsequent hyponatriemia. In nephrotic syndrome, volume retention results either directly from the primary renal disease, which induces renal sodium and volume retention ("overfilling"), or indirectly from the reduced plasma oncotic pressure due to hypoalbuminemia, which induces a fluid shift from the intravascular to the interstitial space ("underfilling") with subsequent acitivation of baroreceptors and secondary sodium and volume retention.
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PMID:[Volume retention in heart failure, nephrotic syndrome, and liver cirrhosis]. 1700 41

A 74-year-old man was diagnosed with nephrotic syndrome due to focal segmental glomerulosclerosis, and steroid therapy was initiated. Subsequently, he was affected by deep mycosis, and hence, voriconazole (VRCZ) was administered. On the 16th day, he was transferred to our hospital because of somnolence and malaise. His systolic blood pressure was approximately 80 mmHg, and he showed decreased skin turgor, indicating volume depletion. Laboratory analysis revealed hyponatremia and liver dysfunction. Discontinuation of VRCZ and drip infusion of normal saline improved the consciousness disorder, hyponatremia, and liver dysfunction. The levels of antidiuretic hormone (ADH) and plasma renin activity were elevated. This patient showed high excreted urine sodium, despite volume depletion and low serum osmolality. Therefore, this patient was diagnosed with salt-losing nephropathy (SLN). SLN should be considered for treatment of VRCZ-associated hyponatremia, together with syndrome of inappropriate secretion of ADH.
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PMID:Voriconazole-associated salt-losing nephropathy. 2056 73

Antidiuretic hormone (ADH), or arginine vasopressin (AVP), is primarily regulated through plasma osmolarity, as well as non-osmotic stimuli including blood volume and stress. Links between water-electrolyte and carbohydrate metabolism have also been recently demonstrated. AVP acts via the intermediary of three types of receptors: V1a, or V1, which exerts vasoconstrictive effects; pituitary gland V1b, or V3, which participates in the secretion of ACTH; and renal V2, which reduces the excretion of pure water by combining with water channels (aquaporin 2). Antidiuresis syndrome is a form of euvolaemic, hypoosmolar hyponatraemia, which is characterised by a negative free water clearance with inappropriate urine osmolality and intracellular hyper-hydration in the absence of renal, adrenal and thyroid insufficiency. Ninety percent of cases of antidiuresis syndrome occur in association with hypersecretion of vasopressin, while vasopressin is undetectable in 10% of cases. Thus the term "antidiuresis syndrome" is more appropriate than the classic name "syndrome of inappropriate ADH secretion" (SIADH). The clinical symptoms, morbidity and mortality of hyponatraemia are related to its severity, as well as to the rapidity of its onset and duration. Even in cases of moderate hyponatraemia that are considered asymptomatic, there is a very high risk of falls due to gait and attention disorders, as well as rhabdomyolysis, which increases the fracture risk. The aetiological diagnosis of hyponatraemia is based on the analysis of calculated or measured plasma osmolality (POsm), as well as blood volume (skin tenting of dehydration, oedema). Hyperglycaemia and hypertriglyceridaemia lead to hyper- and normoosmolar hyponatraemia, respectively. Salt loss of gastrointestinal, renal, cutaneous and sometimes cerebral origin is hypovolaemic, hypoosmolar hyponatraemia (skin tenting), whereas oedema is present with hypervolaemic, hypoosmolar hyponatraemia of heart failure, nephrotic syndrome and cirrhosis. Some endocrinopathies (glucocorticoid deficiency and hypothyroidism) are associated with euvolaemic, hypoosmolar hyponatraemia, which must be distinguished from SIADH. Independent of adrenal insufficiency, isolated hypoaldosteronism can also be accompanied by hypersecretion of vasopressin secondary to hypovolaemia, which responds to mineralocorticoid administration. The causes of SIADH are classic: neoplastic (notably small-cell lung cancer), iatrogenic (particularly psychoactive drugs, chemotherapy), lung and cerebral. Some causes have been recently described: familial hyponatraemia via X-linked recessive disease caused by an activating mutation of the vasopressin 2 receptor; and corticotropin insufficiency related to drug interference between some inhaled glucocorticoids and cytochrome p450 inhibitors, such as the antiretroviral drugs and itraconazole, etc. SIADH in marathon runners exposes them to a risk of hypotonic encephalopathy with fatal cerebral oedema. SIADH treatment is based on water restriction and demeclocycline. V2 receptor antagonists are still not marketed in France. These aquaretics seem effective clinically and biologically, without demonstrated improvement to date of mortality in eu- and hypervolaemic hyponatraemia. Obviously treatment of a corticotropic deficit, even subtle, should not be overlooked, as well as the introduction of fludrocortisone in isolated hypoaldosteronism and discontinuation of iatrogenic drugs.
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PMID:Hyponatremia and antidiuresis syndrome. 2211 69

Sodium, the most important extracellular fluid electrolyte, is the focus of several homeostatic mechanisms that regulate fluid and electrolyte balance. Hyponatremia is a common electrolyte abnormality caused by an actual sodium deficiency or extracellular compartment fluid excess. Clinical symptoms are related with acuity and speed with which this abnormality is established. The symptoms are mainly neurological and neuromuscular disorders (headache, confusion, stupor, seizures, coma) due to brain cells edema. Hyponatremia due to sodium deficiency is caused by sodium loss from kidney (nephritis, diuretics, mineralocorticoid deficiency) and / or extrarenal (vomiting, diarrhea, burns). Hyponatremia due to water excess seems to be the most common and it is attributable to cirrhosis, nephrotic syndrome, heart failure, infusion 5% glucose solutions and drugs that stimulate ADH secretion. It was recently highlighted the role of inflammation and IL-6 in the non-osmotic ADH release. Hyponatremia is considered also marker of phlogosis. Acute (<48 h) and severe (<125 mEq/ L) hyponatremia is a medical emergency that requires prompt correction. Patients with chronic hyponatremia have a high risk of osmotic demyelination syndrome if rapid correction of the plasmatic sodium occurs. In combination with conventional therapy, a new class of drugs, vasopressin receptors antagonists (AVP-R antagonists) would be able to increase the excretion of electrolyte-free water and the serum sodium concentration.
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PMID:[Hyponatremic syndrome]. 2236 42


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