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 prospective study was undertaken to define the clinical features, natural history and etiology of post-obstructive diuresis. Studied in detail were 8 patients with a massive diuresis after relief of urinary tract obstruction. We found that urea mediated osmotic diuresis, natriuresis owing to elimination of retained sodium from the obstructed phase, tubular defects in sodium reabsorption, renal unresponsiveness to antidiuretic hormone and iatrogenic factors may play varying roles in each individual diuresis. Overzealous fluid replacement should be avoided.
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PMID:Post-obstructive diuresis: a varied syndrome. 111 14

In preparation for the conduct of biochemical experiments in the Skylab Orbital Workshop a study was performed on the stability of various chemical constituents in urine in 2 different techniques for preservation and storage. Urine samples were either vacuum dried or frozen and maintained in storage at minus 20 degrees for periods of up to 10 weeks. The urinary constituents studied included aldosterone, antidiuretic hormone, epinephrine, norepinephrine, urea, nitrogen, creatine, hydroxyproline, 17-hydroxycorticosteroids, calcium, sodium potassium, chloride, magnesium and phosphate. Some degradation of urinary compounds was observed after both treatments. The rate and variability of destruction following the vacuum drying treatment, however, was greater than for freezing. It was concluded that only the freezing treatment could be used to preserve with predictable loss the urinary samples which would be returned to earth following the conclusion of each Skylab flight.
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PMID:Acomparative study of two methods of urine preservation. 112 11

1. Healthy subjects, given a long-acting preparation of vasopressin intramuscularly, excreted a significantly less concentrated urine than when subjected to fluid deprivation for 28 h. 2. When fludrocortisone, a potent mineralocorticoid, was given in addition to vasopressin the urine was not significantly less concentrated than after fluid deprivation. 3. Oral urea-loading also enhanced the urine-concentrating power of vasopressin but its effect was less marked than that of fludrocortisone. Oral urea did not increase further the urine concentration achieved by combined fludrocortisone and vasopressin. 4. Renal concentrating power was assessed in fourteen patients with renal disease and impaired concentrating ability. Fludrocortisone significantly enhanced the urine concentration achieved by vasopressin alone and the resultant urine was not significantly less concentrated than that achieved by fluid deprivation. 5. The action of fludrocortisone in enhancing the urine-concentrating effect of vasopressin is similar to that of aldosterone and is probably due to the increased sequestration of solute in the renal medulla, caused by increased reabsorption of sodium chloride in the ascending limb of the loop of Henle. 6. In the clinical assessment of renal concentrating power, the combined use of fludrocortisone and vasopressin has potential advantages over established methods.
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PMID:Assessment of urine-concentrating ability in man: effect of fludrocortisone and urea in enhancing response to vasopressin. 112 20

The permeability of the tight junctions (zonulae occludentes) was evaluated along the entire length of the collecting duct of the rat using a lanthanum tracer technique. Nine rats with hereditary hypothalamic diabetes insipidus were studied using standard micropuncture and clearance techniques. Glomerular filtration rate (GFR) estimated from inulin clearance, urine and plasma osmolality (U/Posm) and urine flow rate (V) were determined in eight of nine animals. During either sustained diuresis (five animals) or vasopressin-induced antidiuresis (four animals), individual surface convolutions of distal convoluted tubules or early cortical collecting ducts were preserved for ultrastructural examination by intraluminal microperfusion with a glutaraldehyde-formaldehyde fixative followed by a second microperfusion with a lanthanum tracer. Mean GFR during diuresis was 6.31 plus or minus se 0.63 ml/min/kg of body wt and v=797 plus or minus se 108 mul/min/kg or 13.6 plus or minus se 2.2% of the filtered load of water. After administration of exogenous vasopressin, V fell to 311 plus or minus 157 mul/min/kg or 5.2 plus or minus se 3.8% of the filtered load of water and U/Posm rose from 0.658 plus or minus se 0.043 to 2.124 plus or minus 0.454. Tight junctions of cortical and outer medullary segments of the collecting duct resisted lanthanum penetration. Tight junctions of the inner medullary and papillary segments of the collecting duct were freely permeable to lanthanum suggesting the presence of a paracellular shunt pathway for solute and water movement. The results were independent of the presence or absence of vasopressin. Physiological studies have previously demonstrated that cortical and outer medullary segments of the collecting duct have a low urea permeability while inner medullary and papillary segments of the collecting duct have a relatively high urea permeability. The possibility is suggested that urea movement across the inner medullary and papillary segments of the collecting duct may occur, at least in part, via a paracellular pathway formed by the nonoccluding tight junction and the lateral intercellular space.
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PMID:Lanthanum permeability of tight junctions along the collecting duct of the rat. 112 64

The possibility of uphill transport of urea from the collecting ducts of sheep fed diets containing 14% protein (HP) and 4.9% protein (LP) was explored by measuring cortex to papilla and urine to papilla gradients of urea during ethacrynic acid diuresis. Clearance studies were done on adult, unanesthetized, hydropenic, vasopressin infused sheep. Saline was given to compensate for urine loss during ethacrynic acid diuresis. Following a period of antidiuresis, ethacrynic acid administration caused and increase in fractional water excretion to 0.33 (HP) and 0.44 (LP), an increase in fractional sodium excretion to 0.28 (HP) and 0.41 (LP), and an average increase in glomerular filtration rate of 14.7%. Fractional potassium excretion showed no consistent change. Renal concentrating ability and medullary sodium accumulation were inhibited. Antidiuretic LP and HP medullary urea accumulation patterns were lost. However, identical but small ascending cortex to papilla urea gradients remained in the LP and HP animals. There was no significant difference between the urea concentration in urine and papilla tissue water. The results fail to provide support for the presence of active urea transport from the collecting ducts of sheep fed high or low protein diets.
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PMID:Urea and sodium in sheep kidneys during ethacrynic acid diuresis. 116 73

Tetranitromethane reaction with intact ovine lutropin and its isolated subunits was studied using spectrophotometric measurements, amino acid analysis, and isolation of tyrosyl peptides. Tyrosyl residues in the beta subunit (beta37, beta59) did not react with tetranitromethane in the intact hormone, but were nitrated in the isolated subunit. The sequence and extent of reaction of tetranitromethane with the tyrosyl residues in the alpha subunit was alpha21 = alpha92 = alpha93 (in intact hormone or isolated subunit) greater than alpha 41 (reacted in isolated subunit only) greater than alpha 30 (reacted in isolated subunit in 8 M urea only). Polymerization was observed as a side reaction in agreement with previous studies. The degree of polymerization appeared to be related to both primary sequence and tertiary structure, and for lutropin had the relation: alpha subunit (93% polymerized) greater than intact hormone greater than beta subunit (less than 40%). Polymerization observed with vasopressin was significantly greater than with oxytocin; for these peptides the tyrosine residues in the monomeric product were converted to 3-nitrotyrosine. Neither 3-nitrotyrosine nor tyrosine was detected in the polymerized by-products. In the tetranitromethane reaction with intact ovine lutropin, other reaction products charcterized by absorption spectra were found. Peptides isolated from these products lacked the characteristic 428 nm abosrption maxima of 3-nitrotyrosyl peptides and showed instead absorption in the 310 to 350 nm region. Similar products from tetranitromethane reactions with di- and tripeptides containing tyrosine have been observed previously (Boyd, N.D., and Smith, D.B. (1971) Can. J. Biochem, 49, 154-161), but they have not been studied in proteins. A possible relationship to the polymerization side reaction is suggested.
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PMID:Reaction of tetranitromethane with lutropin, oxytocin, and vasopressin. 124 74

The effects of iso-osmolar and hypo-osmolar volume expansion on renal water and sodium excretion were studied in dogs during light chloralose anesthesia. Saline or a hypo-osmolar of glucose and urea was given i.v. (20 ml/kg b.w.t. in 60 min). From the start of this infusion the combined weight of the hydration infusate and the dog was maintained constant by a servo system, which controlled the rate of infusion of a hypo-osmolar solution. Consequently the degree of hydration increased linearly during the infusion period after which it remained constant throughout the experiment. No increase in free water clearance was seen after iso-osmolar volume expansion. The rate of excretion of sodium increased considerably. Hypo-osmolar volume expansion provoked a water diuresis during which the rate of excretion of sodium fell to less than 0.1 mumol/kg b.w.t. min. It is concluded that under the present circumstances infusion of iso-osmolar saline is not associated with a decrease in the rate of secretion of vasopressin.
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PMID:Effects on renal water and sodium excretion of infusions of either iso-osmolar saline or a hypo-osmolar solution of non-electrolytes. 127 14

The effect of bath fluid hypertonicity on hydraulic conductivity (Lp) and [14C]urea permeability (Pu) of the distal inner medullary collecting duct (IMCD) was studied in the absence and in the presence of vasopressin (VP) using the in vitro microperfusion technique of rat IMCD. In the first three groups of IMCD, we observed that in the absence of VP the Lp was not different from zero when the osmotic gradient was created by hypotonic perfusate and isotonic bath fluid, but it was significantly greater than 1.0 x 10(-6) cm.atm-1.s-1 when the osmotic gradient was created by hypertonic bath and isotonic perfusion fluid. The increase in Lp was observed when the hypertonicity of the bath fluid was produced by the addition of NaCl or raffinose, but no such effect was observed with urea. The stimulated effect of bath fluid hypertonicity on Lp was also observed in the IMCD obtained from Brattleboro homozygous rats in which VP is absent. The NaCl hypertonic bath increased the Pu in the absence of VP. In another series of experiments with VP (10(-10) M) we observed that the hypertonic bath fluid increased in a reversible manner the VP-stimulated Lp of distal IMCD. However, the NaCl hypertonicity of the bath fluid was not able to increase dibutyryladenosine 3',5'-cyclic monophosphate-stimulated Lp. The Pu stimulated by VP (10(-10) M) increased twofold when the bath fluid was hypertonic. Therefore hypertonicity of the peritubular fluid produced by the addition of NaCl or raffinose increases the Lp and Pu in the absence and in the presence of VP. No such effect was noted with the addition of urea.
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PMID:Effect of peritubular hypertonicity on water and urea transport of inner medullary collecting duct. 131 42

The vasopressin-regulated urea carrier and the vasopressin-regulated water channel are distinct transporters present in the apical membrane of the inner medullary collecting duct (IMCD) cells. To assess whether these transporters may be activated by common mechanisms, we investigated the time course of increase of urea and water permeability in response to vasopressin in isolated perfused terminal IMCD segments. The permeability responses were determined through the use of a specially designed continuous-flow fluorometer for rapid analysis of collected tubule fluid samples. The time courses of activation of the two transporters by vasopressin were virtually identical. Both urea and water permeability displayed a rapid initial increase for the first 10 min followed by a slower secondary response lasting at least 30 additional min. The lag periods between vasopressin addition and the initial rise in permeability were the same for urea (34.2 +/- 8.8 s) and water (34.8 +/- 8.9 s) transport activation. Furthermore, the initial rate of permeability increase (normalized by the total increase) was not significantly different for the two transport processes. The lag periods for the increase in urea permeability in response to 8-bromoadenosine 3',5'-cyclic monophosphate and vasopressin were not significantly different. The results are consistent with the view that the rate-limiting step in vasopressin-induced activation is the same for both the urea carrier and water channel and may lie at a step beyond generation of adenosine 3',5'-cyclic monophosphate.
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PMID:Kinetics of urea and water permeability activation by vasopressin in rat terminal IMCD. 132 Mar 35

1. Isoprenaline strongly increases the urea permeability of the bladder of Bufo bufo. This effect is due to its interaction with beta 2-adrenoreceptors, activating, in turn, the adenyl cyclase. 2. In order to ensure the regulation of urea permeability, the isoprenaline effect is present even in pathophysiological conditions, inhibiting the vasopressin action.
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PMID:Beta 2-adrenergic regulation of urea permeability of the Bufo bufo bladder. 135 17


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