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)

A highly specific radioimmunoassay for arginine-vasopressin (AVP) in human urine has been developed, with a detection limit of 2.2 fmol/ml. The mean recovery of added AVP was 99.5 +/- 3.1 (S.D.)% when correction was made for the fact that an inverse relationship was observed between the recovery of AVP and the osmolality of the urine. The intra- and interassay coefficients of variation were 3.5--7 and 2.5--10% respectively. Arginine-vasopressin remains stable in urine after repeated freezing and thawing after storage at 4 or 20 degrees C for up to 7 days and at -20 degrees C for more than 3 months. During unrestricted fluid intake in normal people, the mean rate of renal excretion of AVP was 95 +/- 68 (S.D.) fmol/min. An isosmotic reduction of 9% in the plasma volume increased the excretion of AVP to 259 +/- 147 (S.D.) fmol/min. At the height of water-induced diuresis the rate of excretion fell to 70 +/- 28 (S.D.) fmol/min. Fluid deprivation for 18 h produced a moderate but significant increase in mean excretion of AVP, to a value of 116 +/- 67 (S.D.) fmol/min. Patients with compulsive water drinking showed a normal relationship between urine osmolality and the rate of excretion of AVP. In pituitary diabetes insipidus, AVP was undetectable, whereas in hereditary nephrogenic diabetes insipidus a progressive increase in the rate of excretion of AVP was observed in response to dehydration. There was a wide variation in the rate of excretion of AVP (range 126--8704 fmol/min) in patients with unexplained hyponatraemia, presumed to be due to an inappropriate secretion of antidiuretic hormone. Despite this variation, the relationship between urine osmolality and the rate of excretion of AVP clearly differed from that observed in normal people.
J Endocrinol 1978 Dec
PMID:Radioimmunoassay of arginine-vasopressin in human urine and its use in physiological and pathological states. 74 31

Effects of pentagastrin (1-4096 ng/kg), cholecystokinin (1-4096 mU/kg, CCK) and vasopressin (.032-128 mU/kg) on gastrointestinal motility and blood flow, were determined by simultaneous measurement of blood flow (electromagnetic flow probes) to and motor activity (strain gages) of corpus, antrum, duodenum, jejunum, and colon of anesthetized dogs. Antral contractile amplitude was increased by pentagastrin at relatively low doses. Pentagastrin also increased corpus blood flow, corpus tone and antral blood flow. Gastric contractile frequency was least sensitive to pentagastrin. Corpus blood flow was decreased and small intestinal blood flow was increased by cholecystokinin at relatively low doses. CCK also increased small intestinal contractile amplitude and, at higher doses, antral contractile amplitude, and duodenal tone. Time-effect relation and sensitivity were different for the hemodynamic and motor responses to pentagastrin and to cholecystokinin. This shows the lack of correlation between vasoactive and motor-stimulating properties of these drugs. However, strong drug-induced contractions were shown to impede antral blood flow (pentagastrin and CCK) by about 35% and duodenal and jejunal blood flow (CCK) by resp. 70 and 60%. Vasopressin reduced blood flow to stomach and intestines by 50-80%, without affecting gastrointestinal motility.
Arch Int Pharmacodyn Ther 1978 Dec
PMID:Motility and hemodynamics of the canine gastrointestinal tract. Stimulation by pentagastrin, cholecystokinin and vasopressin. 74 69

Hepatocytes isolated from the livers of fed rats were used for a comparative study of the effects of phenylephrine, vasopressin and glucagon on gluconeogenesis and on enzymes of glycogen metabolism. When hepatocytes were incubated in the presence of Ca(2+), phenylephrine stimulated gluconeogenesis from pyruvate less than did glucagon, but, in contrast with this hormone, it did not affect the activities of protein kinase and pyruvate kinase, nor the concentration of phosphoenolpyruvate, and it did not decrease the release of (3)H(2)O from [6-(3)H]glucose. The effects of vasopressin were similar to those of phenylephrine. Gluconeogenesis from fructose was also stimulated by phenylephrine and, more markedly, by glucagon at the expense of the conversion of fructose into lactate. Insulin was able to antagonize the stimulatory effect of phenylephrine on gluconeogenesis from pyruvate. When Ca(2+) was removed from the incubation medium, phenylephrine still stimulated gluconeogenesis from pyruvate, but it also caused an activation of protein kinase and an inactivation of pyruvate kinase; accordingly, the concentration of phosphoenolpyruvate was increased, and, in contrast, vasopressin had no effect on all these parameters. The property of phenylephrine to cause the activation of glycogen phosphorylase was decreased by glucose or by the absence of Ca(2+); it was abolished when these two conditions were combined. Glycogen synthase was inactivated by phenylephrine in the presence or the absence of Ca(2+), although presumably by different mechanisms.
Biochem J 1978 Dec 15
PMID:Control of gluconeogenesis and of enzymes of glycogen metabolism in isolated rat hepatocytes. A parallel study of the effect of phenylephrine and of glucagon. 74 52

1. In hepatocytes from starved rats, vasopressin, angiotensin (angiotensin II) and oxytocin stimulated gluconeogenesis from lactate by 25--50%; minimal effective concentrations were about 0.02pM, 1 nM and 0.2 nM respectively. 2. Vasopressin and angiotensin also stimulated gluconeogenesis from alanine, pyruvate, serine and glycerol. EGTA decreased gluconeogenesis from these substrates. 3. Hormonal stimulation of gluconeogenesis from lactate was abolished in the absence of extracellular Ca2+. 4. Insulin did not prevent stimulation of gluconeogenesis by vasopressin or angiotensin. 5. The potency of the stimulatory effects of vasopressin and angiotensin on hepatic gluconeogenesis suggests they are operative in vivo. Also, the data suggest that Ca2+ plays a role in the stimulation by these hormones.
Biochem J 1978 Dec 15
PMID:Stimulation by vasopressin, angiotensin and oxytocin of gluconeogenesis in hepatocyte suspensions. 74 59

The region of the arginine-vasopressin (AVP) molecule critical for binding to the effective antibodies in a RIA has been localized to the vicinity of the Phe3 position by using the cross-reaction in the assay between AVP and a number of its structural analogs. Binding seems to be almost independent of any direct contributions from components of the tripeptide tail of AVP. Using this RIA it was found that disequilibrium conditions of incubation produce a 5-fold increase in assay sensitivity over equilibrium conditions. Amino acid analysis revealed that three synthetic peptide preparations used as reference standards comprised only 70-80% of their weight as peptide and this finding points up the need to correct such reference standards for their peptide content. The ratio of rat vasopressor activity to RIA activity of these three preparations as well as of a natural AVP preparation, however, approximated unity. Results obtained comparing measurements of AVP in rat neural lobes by RIA and rat vasopressor assay show a correlation between RIA and bioassay of 0.9406, a slope of 1.086, and an intercept of 20 mU, suggesting good agreement for AVP determined by these two assay systems.
Endocrinology 1978 Dec
PMID:Characterization of an antiserum used in a radioimmunoassay for arginine-vasopressin: implications for reference standards. 74 29

Sensitive and highly specific RIAs for arginine vasopressin (AVP) and oxytocin (OT) were utilized to assess the specificity of neurohypophyseal hormone release after hemorrhage or infusion of hypertonic saline to trained conscious dogs. Phlebotomy of 12.5 and 25 ml/kg produced increases in plasma AVP from 1.0 +/- 0.2 to 7.8 +/- 2.1 and 41.6 +/- 9.7 (SEM) microunit/ml respectively, and both responses differed significantly from values in control experiments (P less than 0.01 after the first phlebotomy and P less than 0.001 after the second phlebotomy). Plasma OT concentrations rose from baseline values of 1.1 +/- 0.4 to 3.3 +/- 0.6 and 8.3 +/- 1.7 microunit/ml (P less than 0.005 and P less than 0.001 compared to controls); plasma osmolality and sodium concentrations were unchanged. Both log AVP and log OT were highly correlated with the quantity of blood removed (r = 0.92 and -0.82, each P less than 0.001). Infusion of hypertonic (20g/dl) NaCl (3.4 meq/kg) over 20 min caused plasma osmolality and sodium to rise from 304 +/- 1.0 mosm/kg and 143 +/- 3.0 meq/liter to 316 +/- 1.0 mosm/kg and 150 +/- 3.0 meq/liter (each P less than 0.001). Plasma AVP rose from 1.5 +/- 0.2 to 2.4 +/- 0.2 microunit/ml (P less than 0.0025) and OT rose from 1.2 +/- 0.5 to 2.6 +/- 0.7 microunit/ml (P less than 0.005). The stimulus response ratios (change in log hormone concentration divided by the rise in plasma osmolality) were comparable for both hormones (0.024 +/- 0.006 for AVP and 0.031 +/- 0.008 for OT; P less than 0.4). The data indicate that hemorrhage or hypertonic saline stimulate release of both AVP and OT. After hemorrhage, there is greater stimulation of AVP than OT, whereas there is comparable stimulation of both peptides after hypertonic saline.
Endocrinology 1978 Dec
PMID:The effect of hemorrhage and hypertonic saline upon plasma oxytocin and arginine vasopressin in conscious dogs. 74 39

Effect of vasopressin on intracranial pressure (ICP) was examined by an intraventricular administration of the hormone to a rabbit. ICP was determined at the cisterna magna with a manometer and recorded automatically with a recorder. An injection of over 150 micro U of vasopressin lowered ICP, but there was no clear dose-response relationship of the effect of vasopressin on ICP. When vasopressin was injected intraventricularly after lowering ICP by an intravenous injection of acetazolamide which inhibits the production of cerebrospinal fluid (CSF), an additive effect of the hormone on ICP was observed. The effect of vasopressin on excretion of water in CSF was examined by the determination of drainage of tritiated water injected into the lateral ventricle of a rabbit. Drainage of radioactive water into vein was measured by collection of blood at the internal jugular vein and radioactivity of the plasma was counted. Vasopressin accelerated excretion of tritiated water into vein. These results indicate that vasopressin facilitated drainage of CSF into vein to lower ICP.
Endocrinol Jpn 1978 Dec
PMID:Effect of vasopressin on intracranial pressure of rabbit. 75 5

Resistance to flow through the choledochoduodenal junction was measured during constant perfusion (0.8 ml saline/min). In eight dogs, intermittent positive-pressure ventilation (IPPV) and continuous positive-pressure ventilation (CPPV) were compared. Pressure in the common bile duct was always higher during JPPV than IPPV. With the first application of CPPV the rate of intravenous fluid was adjusted to maintain constant Hct. Mean hepatic venous pressure (Phv) increased from 6.6 to 11.5 cmH2O (P less than 0.001). Mean pressure in the common bile duct increased (P less than 0.001) from 11.6 to 14.1 cmH2O. The average increase in resistance was 21%. Changes reversed with return to IPPV. During the second application of CPPV, intravenous fluid was increased to maintain constant arterial pressure. Phv increased to 12.8 cmH2O and pressure in the common bile duct increased to 15.0 cmH2O (30% increase). In four additional dogs, choledochoduodenal resistance during continuous CPPV was reduced by intravenous vasopressin, intravenous norepinephrine and intraducta phenylephrine. CPPV increases resistance to flow through the choledochoduodenal junction, probably by vascular engorgement.
J Appl Physiol 1975 Dec
PMID:Continuous positive-pressure ventilation and choledochoduodenal flow resistance. 76 14

The effects of norepinephrine, phentalamine, oxytocin, vasopressin, several prostaglandins, and indomethacin on the spontaneous motility of isolated guinea pig cauda epididymidis were explored. Phentolamine and indomethacin reduced the isometric peak tension of spontaneous epididymal contractions. Phentolamine also depressed the frequency. Both findings suggest that catecholamines and endogenous prostaglandins are in some way regulators of the spontaneous motility of the cauda epididymidis. Norepinephrine resulted in the development of a distinct, sustained, tonic contraction without phasic activity, whereas prostaglandins E1, E2, and F2 alpha elicited a tonic increase accompanied by frequent, superimposed, phasic contractions. Both oxytocin and vasopressin comparably enhanced epididymal motility, producing contractile responses similar to those observed with prostaglandins. Since the epididymal contractions can influence the time spent by spermatozoa in passing through the ductus epididymidis, the above-mentioned compounds could play an important role in spermatozoal transport via modulation of epididymal contractile activity. In addition, such naturally occurring substances might regulate the release of sperm from the last portion of the epididymis into the ductus deferens.
Fertil Steril 1975 Dec
PMID:Physiologic and pharmacologic studies on the motility of isolated guinea pig cauda epididymidis. 80 41

Extracellularly recorded action potentials were obtained from hypothalamic supraoptic neurones in unanaesthetized rhesus monkeys. Rates and patterns of firing were studied during an initial control period, during 5 successive days of water deprivation and during 4 further days when drinking water was again available. During water deprivation, plasma osmolarity increased progressively from about 300 mOsmoles/kg to about 340 mOsmoles/kg; control values were again reached after 3 days of rehydration. Systematic changes in action potential firing accompanied the changes in plasma osmolarity. Under control conditions, the majority of cells fire slowly and irregularly (type i), whilst a few cells exhibited phases of alternating activity and silence (type p). As dehydration progresses, the frequency of neuronal firing increase and the pattern of firing changes. By the third day the majority of cells are type p with few type i cells being found. By the fourth day, the population consists of type p cells with some others showing a high continuous rate of firing (type c). By the fifth day, these two cell types are found in approximately equal proportions. Rehydration of the animal reverses the situation. We propose that type i cells contribute little, if at all, to hormone secretion, while type p and type c cells would be in a more actively secreting state. According to this view, the three firing patterns would represent different activity states of the same functional population stimulated by the unspecific stimulus of water deprivation rather than functionally different neurones. However, the use of stimuli which selectively release either oxytocin or vasopressin may be needed to answer this problem.
Brain Res 1975 Dec 19
PMID:Hypothalamic supraoptic neurones: rates and patterns of action potential firing during water deprivation in the unanaesthetized monkey. 81 25


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