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)

Neurohypophyseal blood flow was studied using radiolabelled microspheres in 13 dogs. Hypoxic hypoxia and carbon monoxide hypoxia with similar arterial oxygen contents (CaO2, approximately 8 vol %) were produced. Under conditions of hypoxic hypoxia, 100-200% increases in blood flow in caudate nucleus, white matter, neurohypophysis, and all other brain regions occurred. Similar blood flow responses were observed with carbon monoxide hypoxia in all brain regions except the neurohypophysis. The role of carotid and aortic chemoreceptors in mediating this blood flow response was studied in 6 additional dogs. Similar degrees of hypoxic hypoxia were produced in chemoreceptor-intact and completely denervated animals (CaO2 approximately 8 vol %, PaO2 approximately 33 mm Hg). Hypoxic hypoxia produced a 250% increase in neurohypophyseal blood flow and a concurrent rise in plasma arginine vasopressin from 8 +/- 3 to 52 +/- 8 pg/ml. Chemoreceptor denervation completely inhibited the increase in neurohypophyseal blood flow associated with hypoxic hypoxia. Arginine vasopressin was not increased by hypoxic hypoxia under conditions of complete denervation. A unique role for peripheral chemoreceptors in regulating neurohypophyseal blood flow is postulated.
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PMID:Influence of chemoreceptors on neurohypophyseal blood flow during hypoxic hypoxia. 366 88

Using the intact isolated perfused rat adrenal preparation we have shown for the first time a direct effect of oxytocin on adrenocortical steroid secretion. Oxytocin specifically stimulated aldosterone secretion in a dose-dependent manner with a threshold dose of 1 pmol. Arginine vasopressin was also shown to be a potent stimulus to aldosterone secretion and was additionally found to stimulate inner zone function. Using superfused adrenal cells, the effects of arginine vasopressin were only seen at 10,000 times higher doses than were effective in the intact perfused gland, and oxytocin had no effect at any dose. These results reinforce the hypothesis that tissue integrity is essential for full expression of steroidogenic control mechanisms. We conclude that oxytocin and vasopressin may play a role in the control of steroidogenesis.
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PMID:Oxytocin and arginine vasopressin stimulate steroid secretion by the isolated perfused rat adrenal gland. 367 May 66

Arginine vasopressin (AVP), a potent vasoconstrictor, does not raise arterial pressure in normal humans or neurally intact animals, even during infusions that achieve pathophysiological plasma concentrations. It has been proposed that this is because AVP facilitates the baroreflex control of the circulation. We performed a series of investigations to test this hypothesis, and to determine sites at which AVP might act to augment the baroreflex. In anesthetized rabbits, vasopressin (36 pmol.kg-1.min-1) increased discharge from both medullated and nonmedullated single fibres from aortic baroreceptor nerves during elevations in aortic arch pressure. Similarly, vasopressin (36 pmol.kg-1.min-1) increased the response of left ventricular mechanoreceptor single fibre discharge to elevations of left ventricular end-diastolic pressure. These observations suggest that sensitization of high and low pressure baroreceptors is one mechanism by which vasopressin may facilitate baroreflexes. In a further series of experiments in sinoaortic denervated anesthetized rabbits, vasopressin (18 pmol.kg-1.min-1) facilitated vagally mediated reflex inhibition of renal sympathetic nerve activity during volume expansion. In humans, AVP (0.37 pmol.kg-1.min-1) raised plasma AVP to an antidiuretic level (22 +/- 4 fmol/mL), but did not change blood pressure or the baroreflex control of heart rate or forearm vascular resistance.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Modulation of cardiovascular reflexes by arginine vasopressin. 369 Mar 95

Arginine vasopressin consists of a 20-membered, disulfide-linked macrocyclic ring system called pressinoic acid to which is attached a COOH-terminal tripeptide. The molecular conformation of pressinoic acid has been determined from single crystal x-ray diffraction data. The 20-membered macrocyclic ring, stabilized by two intramolecular hydrogen bonds, has a type I beta-bend centered on Gln4 and Asn5 and a highly distorted type II' bend centered on Phe3 and Gln4. In vasopressin the Asn5 side chain extends away from the macrocyclic ring system and hydrogen bonds to the terminal tripeptide, but in pressinoic acid the Asn5 side chain lies over the molecule and forms a strong hydrogen bond to the nitrogen of Tyr2. The absence of pressor activity in pressinoic acid may be a result of both the loss of the COOH-terminal tripeptide and the incorrect orientation of the Asn5 side chain. Whether this class of hormones has pressor or oxytocic activity is determined by the orientation of the Tyr2 side chain, that is, whether it is extended away from or over the ring system, respectively. In pressinoic acid, the Tyr2 side chain is in the expected "pressor conformation," that is, extended away from the ring system, and is stabilized through a hydrophobic interaction with the Phe3 side chain. Thus, the conformation of the pressinoic acid molecule partly explains the activity of vasopressin-like hormones.
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PMID:Structure of pressinoic acid: the cyclic moiety of vasopressin. 370 48

Guinea pig neurohypophysial hormones have been purified by two procedures, one involving molecular sieving and paper chromatoelectrophoresis, the other high-pressure reverse-phase liquid chromatography. Arginine vasopressin and oxytocin have been identified by their amino acid compositions and their retention times in HPLC determined through their biological properties. No partially processed precursor, including a neurohormone and a neurophysin, has been detected. Because the cleavage of the three-domain vasopressin-neurophysin-copeptin precursor is apparently complete between the first two domains, whereas it is not between the second and the third, it is supposed that two distinct enzymic systems are involved in the processing.
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PMID:Guinea pig neurohypophysial hormones. Peculiar processing of the three-domain vasopressin precursor. 380 79

Arginine vasopressin (AVP) is known to produce increases in total peripheral resistance (TPR) and mean arterial pressure (MAP) and decreases in heart rate (HR), cardiac output (CO), and plasma renin activity (PRA). Some recent observations with AVP and synthetic analogues have suggested that under certain conditions, AVP can induce cardiovascular and reninsecretory responses in the opposite directions. To characterize the receptors mediating these responses, the effects of AVP, oxytocin, and synthetic neurohypophyseal analogues with specific antidiuretic, vasoconstrictor, or oxytocic activities were studied in conscious dogs. AVP and 2-phenylalanine-8-ornithine-oxytocin (Phe2Orn8OT, a selective vasoconstrictor agonist) produced similar responses when infused at 10 ng X kg-1 X min-1. That is, TPR and MAP increased, and CO, HR, and PRA decreased. Pretreatment with a selective vasoconstrictor antagonist, [1-(beta-mercapto-beta,beta-cyclopentamethylenepropionic acid) 2-(O-methyl)tyrosine]AVP, abbreviated d(CH2)5Tyr(Me)-AVP (10 micrograms/kg), blocked the actions of Phe2Orn8OT. However, in the presence of d(CH2)5Tyr(Me)AVP, AVP actually decreased TPR and increased CO, HR, and PRA. An analogue with selective antidiuretic activity, 4-valine-8-D-AVP (VDAVP, 10 ng X kg-1 X min-1), produced the same effects as the combination of vasopressin plus d(CH2)5Tyr(Me)AVP. Neither the effects of VDAVP nor of AVP plus antagonist were blocked by propranolol (1 mg/kg). These data indicate that vasopressin, by its antidiuretic activity, produces cardiovascular effects that are opposite to many of those produced by its vasoconstrictor action and that these effects are not dependent on mediation by beta-adrenoceptors.
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PMID:Hemodynamic effects of neurohypophyseal peptides with antidiuretic activity in dogs. 384 Jun 55

Arginine vasopressin (AVP) is used to treat esophageal variceal hemorrhage but has the drawbacks of rebleeding and reported coronary insufficiencies. In conscious dogs (n = 23) we compared AVP and an analog, triglycyl desamino lysine vasopressin (TDLVP), for arterial pressor responses and changes in regional blood flow. Dogs were infused with saline (n = 5), AVP (n = 7) or TDLVP (n = 7), and blood flow was measured with microspheres during control, infusion and postinfusion in 46 tissue sections including pieces of the esophagus, stomach, liver, kidney, spleen, heart, skin, muscle and brain. TDLVP (1.0 micrograms/kg/min) and AVP (0.025 micrograms/kg/min) produced a similar mean arterial pressure increase of 23 mm Hg and a heart rate decrease of 38 beats/min. TDLVP sustained the increase in mean arterial pressure and reduction in heart rate at 30 min postinfusion whereas AVP did not. Neither AVP nor TDLVP showed a reduction in brain, kidney or liver flow; however, both produced reductions (73 and 61%, respectively, P less than .01) in mucosal-esophageal flow. Only TDLVP reduced mucosal-fundus blood flow (P less than .01). Endocardial flow was reduced (27%) in both TDLVP and AVP groups; however, heart rate also decreased during this time and a linear correlation between these two measurements yielded a value for r2 of 0.83. Thus, TDLVP offers a therapeutic alternative to AVP in treating gastroesophageal varices due to its longer duration of action as represented by the sustained reduction in esophageal and mucosal-fundus flow.
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PMID:Regional blood flow changes in response to mildly pressor doses of triglycyl desamino lysine and arginine vasopressin in the conscious dog. 396 37

The dopaminergic inhibition of the hydrosmotic effect of vasopressin was studied by in vitro perfusion of the cortical collecting tubule isolated from the rabbit kidney. Arginine vasopressin (AVP) 100 microU/ml increased hydrosmotic water permeability (Pf, 10(-3) cm/s) by 11.4 +/- 1.59. Although dopamine 10(-5) M added alone to the bath did not affect Pf, the combined administration of 10(-5) M dopamine and 100 microU/ml AVP reduced the hydrosmotic effect of AVP to to 2.37 +/- 0.34. This inhibitory effect of dopamine was reversed by the simultaneous addition of 10(-5) M metoclopramide, a D2-antagonist. These observations suggest that dopaminergic receptors also exist in the cortical collecting tubule. The dopaminergic inhibition of the hydrosmotic action of AVP may be at least in part responsible for the diuretic action of dopamine.
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PMID:Dopaminergic inhibition of the action of vasopressin on the cortical collecting tubule. 406 4

Five families were studied in which cranial diabetes insipidus occurred. In the pedigrees presented, the disease clearly followed an autosomal dominant mode of inheritance. Linkage analysis was performed in one large family by calculating lod scores for linkage between loci for cranial diabetes insipidus and 18 polymorphic markers and chromosome heteromorphisms. No significant genetic linkage was found and only one of the polymorphic markers gave a positive hint of linkage. A water deprivation test was performed in nine patients from three of the families and in healthy control subjects. The plasma concentration of arginine vasopressin was very low or undetectable in the patients, and unlike the control subjects did not increase significantly during water deprivation. Arginine vasopressin and serum osmolality (Sosm) were significantly positively correlated in the controls, but not in the patients. The results indicated that an arginine vasopressin-level lower than 2 pg/ml strongly suggests a diagnosis of cranial diabetes insipidus if at the same time Sosm is higher than 295 mosmol/kg. Studies with different intranasal dosages of 1-deamino-D-arginine-vasopressin (DDAVP) given once or twice a day showed that 20 micrograms effectively reduced urinary output and that administration once a day could be sufficient.
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PMID:Familial cranial diabetes insipidus: a report of five families. Genetic, diagnostic and therapeutic aspects. 409 58

The timed uptake of (131)I-labelled human serum albumin was used as an index of regional perfusion in the isolated rat kidney.1. Arginine vasopressin in doses of 1, 5 and 10 muu./ml. of perfusate decreased papillary perfusion. Total renal perfusion was decreased only by the 5 muu. dose.2. Ornithine-8-vasopressin in doses of 5 and 10 muu./ml. of perfusate decreased papillary perfusion. Total renal perfusion was decreased only by the 10 muu. dose.3. When the relative viscosity of the perfusate was increased to a value of 2.0 from the control value of 1.7, both papillary perfusion and total renal perfusion were reduced.4. Arginine vasopressin further reduced papillary flow in kidneys perfused with high viscosity artificial plasma.
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PMID:The effect of vasopressin upon the vasculature of the isolated perfused rat kidney. 485 90


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