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)

The mechanisms for the antidiuretic effects of dynorphin (DYN), an endogenous kappa-agonist, microinjected into the hypothalamic supraoptic (SON) and paraventricular (PVN) nuclei were investigated. DYN decreased the urine outflow rate dose-dependently from 5 to 20 nmol in the SON and PVN, and it increased vasopressin release. Microinjection of des-Tyr-DYN (a non-opioid peptide) into the SON produced antidiuretic effects with similar potency to that of the DYN-induced effects. However, in the PVN, the effects of des-Tyr-DYN were very markedly weaker than those of DYN. The DYN-induced antidiureses in the SON were partially inhibited by phenoxybenzamine, timolol and atropine, but not by naloxone. Those in the PVN were partially inhibited by naloxone, timolol and atropine, but not by phenoxybenzamine. Synthetic specific kappa-agonists, U50, 488H and Tyr-Gly-Gly-Phe-Leu-Arg-Arg-Ile-Arg-Pro- Arg-Leu-Arg-Gly 5-aminopentylamide (DAKLI), microinjected into the PVN also produced antidiuretic effects in a dose-dependent manner. The order of antidiuretic potency was DAKLI > DYN > U50,488H, which was the same as that of kappa-receptor binding affinity. The DAKLI-induced antidiureses in the PVN were not inhibited by naloxone. These results suggested that DYN caused antidiureses by vasopressin release, through adrenergic and cholinergic mechanisms in the SON and PVN. Only the DYN-induced effects in the PVN were mediated, at least partially, through opioid receptors, perhaps the kappa-subtype.
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PMID:Microinjection of dynorphin into the supraoptic and paraventricular nuclei produces antidiuretic effects through vasopressin release. 790 54

Previous work showed the existence of receptors for arginine vasopressin (AVP) in the anterior pituitary; these receptors were classified as belonging to a distinct AVP receptor subtype, referred to as AVP-V1b receptors, and are thought to mediate the well documented ACTH-releasing activity of AVP. In the present work, high affinity receptors for another neurohypophyseal hormone, oxytocin (OT), were also shown to be present within the rat anterior pituitary; to this end, [125I]d(CH2)5[Tyr(Me)2Thr4Tyr-NH2(9)]OVT was used as a ligand in receptor binding studies. Experiments on dispersed rat anterior pituitary cells in a superfusion system confirmed earlier reports that OT acts as an additional secretagogue of ACTH, with significant effects first seen at concentrations as low as 1 nM. Further studies addressed the question of whether stimulation of ACTH release is mediated by OT receptors or whether receptors for AVP (V1b receptors) might serve this role. For this, highly selective agonist and antagonist ligands of the OT receptor and nonselective agonist and antagonist ligands of the V1b receptor were employed. Neither the OT receptor agonist Thr4Gly7OT nor the OT receptor antagonist des-Gly(NH2)9d(CH2)5-[Tyr(Me)2 Thr4]OVT displayed any influence on basal ACTH release, and des-Gly(NH2)9d(CH2)5-[Tyr(Me)2Thr4]OVT did not interfere with OT-induced ACTH release; these results indicated that OT promotes ACTH release through a receptor(s) other than the OT receptor itself. Evidence for the involvement of AVP V1b receptors was provided by the observation that the AVP receptor antagonist dP[Tyr(Me2)]AVP completely abolished OT-elicited increases in ACTH release. Thus, AVP V1b receptors mediate the actions of two structurally related peptides on ACTH secretion; the role of OT receptors in adenohypophyseal function remains to be determined.
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PMID:Oxytocin-stimulated release of adrenocorticotropin from the rat pituitary is mediated by arginine vasopressin receptors of the V1b type. 795 27

Arginine vasopressin binding site characterisation was performed on purified nuclei and plasma membranes from livers of Sprague-Dawley rats. [125I][d(CH2)5,Sarc7,Arg8]vasopressin, a selective V1 vasopressin receptor antagonist radioligand, bound to the nuclei in a protein concentration and time dependent manner. Scatchard analysis of nuclear binding sites revealed a single binding site with maximal binding site density (Bmax) of 115 +/- 13 fmol/mg protein and affinity (KD) of 5.2 +/- 0.7 nM. Plasma membrane binding demonstrated a Bmax of 529 +/- 25 fmol/mg protein and KD of 1.9 +/- 0.1 nM. The displacement profile for nuclear binding sites using vasopressin analogues was similar to that for plasma membrane binding sites and was typical of a V1 vasopressin receptor type. There was no evidence of V2-like vasopressin receptor binding using [3H]des-Gly-NH9(2)[d(CH2)5,D-Ile2,Ile4,Arg8]vasopressi n, a selective V2 vasopressin receptor radioligand, in the nuclear or membrane fractions. These results suggest the existence of nuclear V1-like vasopressin binding sites.
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PMID:V1-like [Arg8]vasopressin binding sites occur in rat hepatocyte nuclei. 798 62

Two series of experiments were done to investigate the mechanism underlying arginine8-vasopressin (AVP)-induced barrel rotation in rats. In the first series, the effect of intracerebroventricular (ICV) administration of various neurohypophyseal hormone antagonists on AVP-induced barrel rotation was studied. The more vasopressin was given, the more the rats exhibited barrel rotation. ICV pretreatment with a V1 vasopressin receptor antagonist, d(CH2)5[Tyr(Me)2]AVP, prevented barrel rotation, while similar treatment with a V2-antagonist, d(CH2)5[dIle2Ile4]AVP, did not affect vasopressin-induced barrel rotation. However, Des-Gly,NH2d(CH2)5[Tyr)Me2)Thr4Orn8]-vasotocin, a specific oxytocin antagonist, potentiated the effect of AVP on barrel rotation. The second experiment was performed in rats equipped with a telemetry system to measure heart rate (HR), core temperature (CT), and gross locomotor activity. Also, in this experiment the incidence of AVP-induced barrel rotation was dose-dependent, as was the number of rats that died. Barrel rotation was accompanied by a significant decrease in CT and HR, while rats that did not develop hypothermia did not show barrel rotation. These results suggest that a V1 receptor is involved in barrel rotation. Since AVP-induced hypothermia is also mediated by a V1 receptor, it is postulated that hypothermia is a prerequisite for barrel rotation to occur. Further experiments are needed to substantiate this hypothesis.
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PMID:Barrel rotation induced by central arginine8-vasopressin treatment: involvement of neurohypophyseal peptide receptors. 811 25

An oxytocin-vasopressin-related peptide, Cys-Phe-Val-Arg-Asn-Cys-Pro-Thr-Gly-NH2, was isolated from the lumbricid earthworm, Eisenia foetida and termed annectocin. Annetocin potentiated not only spontaneous contractions of the gut but also pulsatory contractions and bladder-shaking movement of the nephridia. Annetocin may be involved in osmoregulation of the animal through nephridial function.
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PMID:Annetocin: an oxytocin-related peptide isolated from the earthworm, Eisenia foetida. 829 46

Previous work has shown that a peptide related to arginine vasopressin is present in the suboesophageal ganglion of the locust, Locusta migratoria. This peptide was determined to be an anti-parallel dimer of the nonapeptide Cys-Leu-Ile-Thr-Asn-Cys-Pro-Arg-Gly-NH2 and was reported to stimulate cyclic AMP production and fluid secretion in a combined Malpighian tubules and midgut preparation from locusts. For these reasons the peptide has been called the arginine-vasopressin-like insect diuretic hormone (AVP-like IDH). Recently, a second diuretic peptide (Locusta-DP), which is related to corticotropin releasing factor, has been identified: this is a potent stimulant of fluid secretion and cyclic AMP production by isolated locust tubules. Because water balance in insects is likely to be controlled by a cocktail of hormones acting on both Malpighian tubules and hindgut, this study directly compares the activity of these two peptides in fluid secretion and cyclic AMP production bioassays on one target organ, the isolated Malpighian tubule of Locusta migratoria. Locusta-DP was synthesised directly, whereas the dimeric AVP-like IDH was obtained by oxidation of a synthetic nonapeptide monomer. Products were separated by RP-HPLC and their structures unequivocally confirmed by enzymatic digestion, sequence analysis and electrospray mass spectrometry. We show that Locusta-DP causes strong stimulation of fluid secretion and cyclic AMP production, whereas the AVP-like IDH has no effect in either assay. These findings are discussed in the light of recent work on the anatomy and physiology of the vasopressin-like immunoreactive (VPLI) neurones in the suboesophageal ganglion of Locusta migratoria, the proposed source of the AVP-like peptide.
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PMID:A comparison of the effects of two putative diuretic hormones from Locusta migratoria on isolated locust malpighian tubules. 838 30

The neurohypophyseal peptide hormone arginine-vasopressin functions as a neuropeptide in several brain areas in addition to its role as a posterior pituitary hormone. Several studies indicate that arginine-vasopressin and arginine-vasopressin receptors appear early in the infant rat brain. To determine if arginine-vasopressin receptors in the infant were responsive to exogenous peptides, we compared the behavioral effects of central or peripheral administration of arginine-vasopressin, arginine vasotocin, the oxytocin precursor oxytocin-Gly-Lys-Arg, and arginine-vasopressin receptor antagonists in socially isolated rat pups. Central administration of arginine-vasopressin decreased the number of rat pup ultrasonic vocalizations, reduced locomotor activity and decreased the latency to express a response to negative geotaxis. Temperature was also reduced at all doses tested. Co-administration of arginine-vasopressin and receptor antagonists suggested that changes in vocal behavior were mediated by the V1 receptor subtype. Changes in core temperature appeared to be mediated by a V2 receptor subtype. Peripheral arginine-vasopressin administration increased calling and decreased core body temperature. Neither effect was blocked by central receptor antagonist administration. The results are consistent with the hypothesis that arginine-vasopressin receptors in the infant rat brain are functional.
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PMID:Effects of central vasopressin administration to infant rats. 847 38

The ferrets' responsiveness to several known and putative emetic agents was evaluated using a variety of agents that were injected subcutaneously and/or intravenously. Apomorphine was consistently emetic at relatively high doses (100 micrograms/kg) when injected subcutaneously in large male ferrets (> or = 1.4 kg). The responsiveness to apomorphine was anomalous in that subcutaneous injections produced a more consistent response than intravenous ones. In addition, ferrets rapidly become tolerant or tachyphylactic to subcutaneously administered apomorphine. Area postrema ablation, but not abdominal vagotomy, rendered ferrets refractory to the emetic effects of apomorphine. This species, relative to dog and humans, proved to be insensitive to a variety of pharmacologic agents including angiotensin II, gastrin, histamine, Leu-enkephalin, neurotensin, serotonin, and vasopressin. Cisplatin elicited forceful retching and emesis. Emetic responses were obtained with substance P and Met-enkephalin in individual animals but were inconsistent. Sensitivity to DAGO [D-Ala2,MePhe4,Gly-ol5 enkephalin] was variable. Results of this study indicate that the ferret is not an optimal model for all forms of emesis.
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PMID:Behavioral studies of emetic sensitivity in the ferret. 849 72

The biological properties of vasotocin, hydrin 1 (vasotocinyl-Gly-Lys-Arg) and hydrin 2 (vasotocinyl-Gly), in particular the hydro-osmotic activities on the frog skin, the frog urinary bladder and the frog kidney, have been compared. Hydrins are as active or more active than vasotocin on the first two organs but they are virtually devoid of antidiuretic activity in the rat and the frog, in contrast to vasotocin. It appears that where the oxytocin ring (residues 1-6), present in the three peptides, is necessary for the action on the three organs, the C-terminal amidated group of vasotocin is necessary for the renal receptor but not for the skin and bladder receptors. It is known that amphibians have two types of vasotocin receptors, V1 and V2, homologous to the vascular/hepatic V1 and the renal V2 vasopressin receptors of mammals, respectively. We suggest that adaptation has led to specialization of (at least) two subtypes of hydro-osmotic V2 receptors, the renal subtype on which vasotocin is mainly active for the reabsorption of tubular water, and the skin/bladder subtype on which hydrin 2 is specifically involved in ensuring the rehydration of the animal. Cooperative evolution might have created in anuran Amphibia, on the one hand, two hydro-osmotic peptides, vasotocin and hydrin 2, derived from a single precursor through differential processing; and on the other hand, two corresponding receptors in kidney and skin for internal and external water recovery.
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PMID:Distinct hydro-osmotic receptors for the neurohypophysial peptides vasotocin and hydrins in the frog Rana esculenta. 858 66

Aquaporin-2 (AQP-2) is a vasopressin-regulated water channel in the kidney collecting duct. AQP-2 is selectively permeable to water molecule and is translocated between the apical membrane and subapical endosomes in response to vasopressin. To investigate the localization and structure of the aqueous pathway of the AQP-2 water channel, a series of site-directed mutants was constructed and functionally analyzed. Insertion of N-glycosylation reporter sequence into each hydrophilic loop (HL) indicated that AQP-2 has a six-membrane spanning topology and that insertional mutations in HL-2 or HL-5 do not alter water channel function. Mercury-sensitive site of AQP-2 is located near the second asparagine-proline-alanine (NPA) domain at cysteine 181, but not near the first NPA domain. Replacement of HL-3 or HL-4 with the corresponding part of Escherichia coli glycerol facilitator abolished water channel function without changing plasma membrane expression of the channel protein. Introduction of cysteine residues in His-122, Asn-123, Gly-154, Asp-155, or Asn-156 induced partial mercury sensitivity, and point mutations in asparagine 123 significantly altered water permeability. Our results implicate that the structure of AQP-2 is different from models previously proposed for AQP-1 and that HL-3 and HL-4 are closely located to the aqueous pathway.
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PMID:Structure of aquaporin-2 vasopressin water channel. 861 98


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