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

Arginine vasopressin (AVP) receptors are expressed early in the developing spinal cord. To characterize AVP-induced conductances in lower thoracic sympathetic preganglionic (SPN) and other lateral horn neurons, we used patch-clamp recording techniques in neonatal (11-21 days) rat spinal cord slices. Most (90%) of 273 neurons, including all 68 SPNs, responded to AVP with membrane depolarization and/or a V1 receptor-mediated, dose-dependent (0.01-1.0 microM) and tetrodotoxin (TTX)-resistant inward current. A role for G-proteins was indicated by persistence of this inward current after intracellular dialysis with GTP-gamma-S or GMP-PNP, its marked reduction with GDP-beta-S, and significant reduction, but not abolition, after preincubation with pertussis toxin or in the presence of N-ethylmaleimide. Analysis of individual current-voltage (I-V) relationships in 57 cells indicated the presence of two different membrane conductances. In 21 cells, net AVP-induced currents reversed around -103 mV, reflecting reduction in one or more barium-sensitive potassium conductances; in 12 cells, net AVP-induced current reversed around -40 mV and was not significantly sensitive to several potassium channel blockers including barium, tetraethylammonium chloride (TEA), 4-aminopyridine (4AP), cesium, or glibenclamide, suggesting increase in a nonselective cationic conductance that was separate from Ih; in 24 cells where I-V lines shifted in parallel, AVP-induced inward currents were significantly greater and probably involved both conductances. These data indicate that SPNs and a majority of unidentified neonatal lateral horn neurons possess functional G-protein-coupled V1-type vasopressin receptors. The wide distribution of AVP receptors in neonatal spinal lateral column cells suggests a role that may extend beyond involvement in regulation of autonomic nervous system function.
 ...
PMID:Vasopressin-induced currents in rat neonatal spinal lateral horn neurons are G-protein mediated and involve two conductances. 977 48

The release of adrenocorticotropin (ACTH) from the corticotrophs is controlled principally by vasopressin and corticotropin-releasing hormone (CRH). Oxytocin may augment the release of ACTH under certain conditions, whereas atrial natriuretic peptide acts as a corticotropin release-inhibiting factor to inhibit ACTH release by direct action on the pituitary. Glucocorticoids act on their receptors within the hypothalamus and anterior pituitary gland to suppress the release of vasopressin and CRH and the release of ACTH in response to these neuropeptides. CRH neurons in the paraventricular nucleus also project to the cerebral cortex and subcortical regions and to the locus ceruleus (LC) in the brain stem. Cortical influences via the limbic system and possibly the LC augment CRH release during emotional stress, whereas peripheral input by pain and other sensory impulses to the LC causes stimulation of the noradrenergic neurons located there that project their axons to the CRH neurons stimulating them by alpha-adrenergic receptors. A muscarinic cholinergic receptor is interposed between the alpha-receptors and nitric oxidergic interneurons which release nitric oxide that activates CRH release by activation of cyclic guanosine monophosphate, cyclooxygenase, lipoxygenase and epoxygenase. Vasopressin release during stress may be similarly mediated. Vasopressin augments the release of CRH from the hypothalamus and also augments the action of CRH on the pituitary. CRH exerts a positive ultrashort loop feedback to stimulate its own release during stress, possibly by stimulating the LC noradrenergic neurons whose axons project to the paraventricular nucleus to augment the release of CRH.
 ...
PMID:Role of the hypothalamic pituitary adrenal axis in the control of the response to stress and infection. 1100 12

During the Altair MIR '93 mission we studied several parameters involved in blood volume regulation. The experiment was done on two cosmonauts before (B-60, B-30), during (D6, D12, D18 for French and D7, D12, D17 for Russian) and after the flight (R+1, R+3 and R+7). Space flight durations were different for two cosmonauts: for the Russian the flight duration was 198 days and for the French 21 days. On board the MIR station only urinary (volume and electrolytes, atrial natriuretic peptide (ANP), cyclic guanosine monophosphate (cGMP) and catecholamines) and salivary (cGMP and cortisol) samples were collected, centrifuged and stored in freezer. Lithium was used as a tracer to know exactly the 24 h urine output (CNES urine collection Kit). Before and after flight, blood was drawn with an epicite needle and vacutainer system for hormonal assays (renin, antidiuretic hormone, cGMP, ANP and aldosterone) in two positions: after 30 min rest in upright seated position and after 90 min of supine position. Salivary samples were collected simultaneously. During flight a decrease of diuresis and ANP and an increase of osmolality were found. No modifications of hematocrit, but an increase of salivary cGMP and cortisol were also observed. The decrease of urinary ANP is in favor of hypovolemia as described in previous flights. The postflight examinations revealed changes in fluid-electrolyte metabolism which indicate a hypohydration status and a stimulation of hormonal system responsible for water and electrolyte retention in order to readapt to the normal gravity.
 ...
PMID:Blood volume regulating hormones, fluid and electrolyte modifications during 21 and 198-day space flights (Altair-MIR 1993). 1154 Oct 10

The suprachiasmatic nucleus (SCN) contains the primary mammalian circadian clock. This clock is entrained to environmental rhythms by external stimuli called zeitgebers. This entrainment is accomplished by the activation of specific, interacting signal transduction cascades. Since a cyclic guanosine monophosphate-dependent mechanism play a crucial functional role for light entrainment in the late night and for transmission of cholinergic stimuli, we examined the expression of protein kinase (PKG) in the rat SCN by means of qualitative and semi-quantitative immunocytochemistry. Immunoreaction (IR) for the isozyme protein kinase G I (PKG I) was found in the dorsomedial part of the SCN considered as an important relay in the output pathways of the clock. Within the SCN, PKG-I IR was colocalized with arginine-vasopressin-IR. The intensities of the PKG-I-IR did not vary between day and night.
 ...
PMID:Protein kinase G I immunoreaction is colocalized with arginine-vasopressin immunoreaction in the rat suprachiasmatic nucleus. 1243 86

Combined therapy with lozartan and metoprolol in patients with chronic cardiac insufficiency has a consistent effect on the levels of epinephrine, angoitensin II, vasopressin, atrial naturiuretic factor, insulin, endothelline, thromboxane B2, guanosine monophosphate, 6-keto prostaglandin F1 alpha, and bradikinin. As to norepinephrine, there has been noted an inconsistent therapeutic effect. It is suggested that the time-related course of a long-term therapy might be associated with a formation of the aldosterone "escape" phenomenon.
 ...
PMID:[Stability of neurohumoral effects of losartan combined with metoprolol in chronic cardiac low output]. 1258 23

We reported previously that sodium nitroprusside (SNP) applied to the anteroventral third ventricular region (AV3V), a pivotal area for autonomic functions, facilitates vasopressin (AVP) secretion in conscious rats. The aim of this study was to pursue the problems of whether nitric oxide (NO) generated from the agent may be responsible for the phenomenon, and whether it may be mediated by cyclic guanosine monophosphate (cGMP), the biosynthesis of which could reportedly be activated by NO. The infusion of SNP into the AV3V of conscious rats produced dose-related increases in plasma AVP, the maximal responses of which appeared at 5 min. Blood pressure and heart rate tended to rise at 15 min. The plasma osmolality, sodium, potassium or chloride did not show marked alteration following the SNP administration. Although the SNP solution was hypertonic and hypernatremic, AV3V application of hypertonic saline with a relatively higher osmolality and an equal sodium level was significantly less effective in augmenting plasma AVP. When injected into the lateral ventricle, SNP did not change plasma AVP and reduced arterial pressure, different from the results provoked by the AV3V application. The rise in plasma AVP in response to the AV3V application of SNP was diminished by preadministration of hemoglobin, a scavenger of NO, that did not affect the responses of the other variables. In contrast, pretreatment with methylene blue, an agent capable of antagonizing the potency of NO to activate guanylate cyclase, did not attenuate but potentiated the responses of both plasma AVP and arterial pressure to the AV3V infusion of SNP. Hemoglobin or methylene blue given alone into the AV3V did not affect any of the variables monitored. On the other hand, the AV3V injection of 8-bromo cGMP, a stable analogue of cGMP, was not potent for causing a significant rise in plasma AVP, in contrast to the notable AVP-enhancing effect of 8-bromo cAMP. Arterial pressure and heart rate were elevated by both of these agents, whereas the remaining variables were not altered. Histological inspection indicated that the infusion sites of the drugs in the AV3V had included areas such as the organum vasculosum of the lamina terminalis, median preoptic nucleus, medial preoptic nucleus and periventricular nucleus. On the basis of these results, we concluded that the AVP secretion prompted by the AV3V application of SNP may be attributable to NO, whereas its well-known ability to stimulate guanylate cyclase activity may hardly contribute to this phenomenon.
 ...
PMID:A study on the mechanism by which sodium nitroprusside, a nitric oxide donor, applied to the anteroventral third ventricular region provokes facilitation of vasopressin secretion in conscious rats. 1264 62

Endothelin is a recently discovered peptide composed of 21 amino acids. There are three endothelin isomers: endothelin-1 (ET-1), endothelin-2 (ET-2) and endothelin- 3 (ET-3). In humans and animals levels of ET-1, ET-2, ET-3 and big endothelin in blood range from 0,3 to 3 pg/ml. ET-1, ET-2 and ET-3 act by binding to receptors. Two main types of the receptors for endothelins exist and they are referred to as A and B type receptors. Different factors can stimulate or inhibit production of endothelin by endothelial cells. Mechanical stimulation of endothelium, thrombin, calcium ions, epinephrine, angiotensin II, vasopressin, dopamine, cytokines, growth factors stimulate the production of endothelin whereas nitric oxide, cyclic guanosine monophosphate, atrial natriuretic peptide, prostacyclin, bradykinin inhibit its production. Endothelins have different physiological roles in human body but at the same time their actions are involved in the pathogenesis of many diseases. The aim of this review was to present some of, so far, the best studied physiological roles of endothelin and to summarize evidence supporting the potential role of ET in the pathogenesis of certain diseases.
 ...
PMID:Endothelin in health and disease. 1562 9

ATP stimulates vasopressin (VP) release from explants of the hypothalamo-neurohypophyseal system (HNS), but the response is not sustained for the duration of exposure to ATP. Since adenosine, a metabolite of ATP, inhibits VP release from neurohypophysial terminals and adenosine receptors (AR) are expressed in supraoptic nucleus (SON) neurons, we postulated that conversion of ATP to adenosine contributed to termination of ATP-stimulated VP release from HNS explants. This was tested using a non-selective AR antagonist, 5-amino-9-chloro-2-(2-furyl)-1, 2, 4-triazolo [1, 5-c] quinazoline (CGS-15943). CGS-15943 did not affect basal VP release and did not alter the initial response to ATP. A selective A1R antagonist, 8-cyclopentyl-1, 3-dipropylxanthine (DPCPX), increased basal VP release at 1 microM, without altering the response to ATP. However, at a higher concentration of DPCPX (10 microM), VP release was enhanced by ATP for an extended period of time. Inhibition of the enzymatic conversion of ATP to adenosine using a combination of a potent ecto-5'-nucleotidase inhibitor, alpha,beta-methylene adenosine 5'-diphosphate (AMP-CP), and a competitive substrate for ecto-5'-nucleotidase (guanosine monophosphate, GMP) did not affect basal VP release. Enzymatic inhibition did slightly prolong the response to ATP, but it was not sustained for the duration of exposure to ATP. We conclude that an endogenous inhibitory influence of adenosine decreases basal VP release from HNS explants and that conversion of exogenously applied ATP to adenosine contributes to termination of ATP-induced stimulation of VP release, but additional mechanisms such as receptor desensitization also limit the response to extended exposure to ATP.
 ...
PMID:Does conversion of ATP to adenosine terminate ATP-stimulated vasopressin release from hypothalamo-neurohypophyseal explants? 1589 96

Water reabsorption in the kidney represents a critical physiological event in the maintenance of body water homeostasis. This highly regulated process relies largely on vasopressin (VP) action and on the VP-sensitive water channel (AQP2) that is expressed in principal cells of the kidney collecting duct. Defects in the VP signaling pathway and/or in AQP2 cell surface expression can lead to an inappropriate reduction in renal water reabsorption and the development of nephrogenic diabetes insipidus, a disease characterized by polyuria and polydipsia. This review focuses on the major regulatory steps that are involved in AQP2 trafficking and function. Specifically, we begin with a discussion on VP-receptor-independent mechanisms of AQP2 trafficking, with special emphasis on the nitric oxide-cyclic guanosine monophosphate signaling pathway, followed by a review of the mechanisms that govern AQP2 endocytosis and exocytosis. We then discuss emerging data illustrating roles played by the actin cytoskeleton on AQP2 trafficking, and lastly we consider elements that affect AQP2 protein expression in cells. Recent advances in each topic are summarized and are presented in the context of their potential to serve as a basis for the development of novel therapies that may ultimately improve life quality of nephrogenic diabetes insipidus patients.
 ...
PMID:Bypassing vasopressin receptor signaling pathways in nephrogenic diabetes insipidus. 1851 87

We present two cases of catecholamine-refractory and vasopressin-refractory vasoplegic syndrome associated with intraoperative anaphylaxis during cardiac surgery. One case was related to the administration of protamine and the other case to the administration of aprotinin. Both cases were successfully managed using intravenous methylene blue. The use of methylene blue blocks accumulation of cyclic guanosine monophosphate by competitively inhibiting the enzyme guanylate cyclase. This results in reduced responsiveness of the vasculature to cyclic guanosine monophosphate-mediated vasodilators, such as nitric oxide. This report provides a description of severe anaphylaxis induced by different agents, in which the use of methylene blue was associated with a significant clinical response.
 ...
PMID:Use of methylene blue for catecholamine-refractory vasoplegia from protamine and aprotinin. 1916 6


<< Previous 1 2 3 4 Next >>