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 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

The responsiveness of conventional and germfree rat aortas and portal veins to vasoactive agents were compared in vitro. The results indicate: (1) aortas and portal veins from germfree rats exhibit an attenuated reactivity to angiotensin, vasopressin and epinephrine but not to KC1; (2) the dose-response curves for epinephrine and the peptides were shifted to the right concomitant with a decrease in maximum contractile tension, and (3) CaC12 dose-response curves obtained on potassium-depolarized aorta were not different from one another, whereas those obtained on portal veins from germfree animals were shifted to the right with a concomitant decrease in maximum response. In addition, aortas and portal veins from germfree rats were found to exhibit a higher total Ca content (but not Mg or water) when compared to conventional animals.
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PMID:Reactivity of aorta and portal vein in germfree rats. 117 11

Acute volume expansion was produced in 9 dogs by infusing a lactated Ringer's solution at 1 ml/kg/min in a volume estimated to increase blood volume by 20%. Volume expansion was maintained by replacing urinary fluid losses with equal volumes of the Ringer's solution. Following volume expansion, the effects of a slow, nonhypotensive hemorrhage on plasma antidiuretic hormone concentration (PADH) were determined and compared to a group of 9 normovolemic dogs subjected to the same hemorrhage procedure, in order to determine if volume receptor control of ADH release would adapt to acute increases in blood volume. Ringer's infusion significantly increased blood volume to 95.2 +/- 3.1 ml/kg (mean +/- SE; P less than 0.01) when compared to a mean normovolemic blood volume of 77.6 +/- 3.4 ml/kg. Volume expansion was associated with a significantly lower PADH (3.2 +/- 1.6 muU/ml) than that in normovolemic dogs (5.7 +/- 1.2 muU/ml; p less than 0.05). Significant increases in PADH (P less than 0.05) occurred in both groups of dogs after 20 and 40 minutes of a continuous, nonhypotensive hemorrhage (0.40 to 0.45 mg/kg/min. Hemmorrhage was also associated with significant decrease in effective left atrial pressure in both groups of dogs after 5, 10, 20, and 40 minutes of hemorrhage (P less than 0.01). There were no significant differences between the two groups of dogs nor were there any significant changes during the experiment within each group for mean arterial blood pressure, arterial pulse pressure, plasma osmolality, plasma sodium concentration and plasma potassium concentration. Effective left atrial pressure and PADH were found to be exponentially correlated with blood volume in bothy hypervolemic and normovolemic dogs. Analysis of covariance of these correlations suggested that the hypervolemic dogs exhibited the same exponential changes in PADH and effective left atrial pressure with decreased blood volume as in the normovolemic dogs. It is concluded that acute volume expansion does not alter volume control of plasma ADH concentration.
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PMID:Volume control of plasma antidiuretic hormone concentration following acute blood volume expansion in the anesthetized dog. 119 3

Studies were performed in the rat to determine the effect of lithium on electrolyte transport in distal portions of the nephron since steep corticomedullary gradient for lithium has been demonstrated and ionic competition and/or substitution of lithium for sodium and potassium may play a role in inhibition of vasopressin-induced water transport. During the intravenous infusion of LiC1, in the absence of volume expansion and at plasma levels of 2-5 mequiv/liter of Li, maximum urine con-entration was inhibitied. Under the same conditions lithium administration impaired potassium secretion and urinary acidification and resulted in a natriuresis. These results indicate that lithium affects electrolyte transport in the same nephron segments in which the action of vasopressin is inhibitied. In addition, evidence is provided that suggests that during the chronic administration of LiC1, the sustained increase in oral intake of water and urinary flow rate results from an increase in thirst as well as reduced renal concentrating ability.
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PMID:Effect of lithium on water and electrolyte metabolism. 120 60

1. In order to study the effect of overhydration on body potassium, experiments were performed on pair-fed rabbits, one of which was maintained continuously on vasopressin and given extra water (60-90 ml day-1 kg-1) for 6-8 days, while the other served as control. 2. Overhydrated rabbits excreted significantly more potassium (53%) in their urine than control rabbits and accumulated a mean potassium deficit of 65-0 mmol, significantly higher than the mean value of 37-1 mmol in the control rabbits. 3. In the overhydrated rabbits, potassium fell significantly in both erythrocytes, from 266 to 173 mmol/kg of dry cells, and also in muscle, from 435 to 341 mmol/kg of fat-free dry solids. Neither changed significantly in the control animals. 4. Overhydration in the presence of vasopressin leads to potassium depletion in the rabbit and a similar phenomenon might be expected in man. Potassium depletion due to overhydration might account for the hypokalaemia and reduction in exchangeable potassium observed in some patients with the syndrome of inappropriate secretion of antidiuretic hormone.
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PMID:Potassium depletion induced by vasopressin and overhydration in the rabbit. 120 83

The purpose of this study was to determine whether centrally administered renin stimulated vasopressin secretion. Vasopressin was not measured directly, but, instead, changes in urinary water excretion in anesthesized dogs undergoing a water excretion in anesthetized dogs undergoing a water diuresis were used as an index of changes in vasopressin secretion. Intraventricular injection of hog renin in a dose of 0.1 Goldblatt unit produced a marked decrease in urine flow which was associated with a decrease in free water clearance and an increase in urinary osmolatiy with no change in osmolar clearance. Sodium excretion increased significantly but there was no change in potassium excretion. These effects, which closely resemble those resulting from an increase in vasopressin secretion, were prevented by hypophysectomy. The antidiuretic effect clearly resulted from an action of renin in the central nervous system since renin had no effect on urine flow or osmolality when administered intravenously. Intraventricular administration of saralasin acetate, a specific antagonist of angiotensin II, completely blocked the effects of intraventricular renin indicating that these effects were mediated via the formation of angiotensin II. The data therefore indicate that there is an interaction between injected renin, brain angiotensinogen, and converting enzyme resulting in the formation of angiotensin II which stimulates the secretion of vasopressin. Additional studies are required to determine whether the brain renin-angiotensin system plays a physiological role in the regulation of a vasopressin secretion.
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PMID:Antidiuresis produced by injection of renin into the third cerebral ventricle of the dog. 124 51

Brain death is associated with loss of hypothalamic, pituitary and brain stem function resulting in apnea, bradycardia and hypotension, poikilothermia, and diabetes insipidus. In order to preserve body functions mechanical ventilation is continued with the aim to maintain an arterial partial pressure of oxygen of more than 100 mmHg. Previous fluid restrictions and the application of diuretics during the treatment of high intracranial pressure frequently result in dehydration. Progressive vasodilation may induce severe hypotension and fluid replacement with cristalloids and if necessary colloids may be called for until the central venous pressure reaches 10 cm H2O. Continuous substitution of potassium and the use of hypotonic solutions such as glucose 5% may avoid hypokalaemia and hypernatraemia, respectively. Inotropic support with dopamine (5-10 micrograms/kg.min) or adrenaline (0.01-0.1 micrograms/kg.min) may be needed to maintain normal mean arterial blood pressure (65 mmHg). Polyuria (5000 ml/24 h) can be treated by continuous intravenous infusion of antidiuretic hormone (0.5-2-10 U/h). Hypothermia must be prevented by warming all fluids (37 degrees C) and covering the patient with heat saving blankets.
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PMID:[Management of the organ donor]. 128 68

We examined the acute effects of bilateral subdiaphragmatic vagotomy (BSV) on blood pressure and renal function in female Sprague-Dawley rats. Mean arterial pressure was greater (p < 0.0001) in rats with BSV than in sham-operated rats (SOR). Rats with BSV had a significantly lower effective renal plasma flow (p < 0.01), total sodium excretion (p < 0.005), fractional sodium excretion (p < 0.01), urine flow (p < 0.01), and fractional excretion of water (p < 0.02) than SOR. The glomerular filtration rate was not significantly different between the 2 groups of rats. Plasma potassium was greater in rats with BSV than in SOR (p < 0.02). Pretreatment with an inhibitor of the angiotensin-converting enzyme prevented the above changes in rats with BSV. Changes in renal function and mean arterial pressure could not be attributed to antidiuretic hormone since plasma levels of antidiuretic hormone were lower in rats with BSV than in SOR (p < 0.002). In addition, the activity of the sympathetic system was decreased in rats with BSV, as suggested by the lower plasma levels of epinephrine (p < 0.003) and norepinephrine (p < 0.02) and the significantly lower renal tissue concentrations of norepinephrine (p < 0.03). No significant changes in renal tissue concentrations of acetylcholine or choline, its precursor, were observed in BSV rats when compared to SOR, suggesting a lack of renal parasympathetic innervation. Plasma renin activity was lower in rats with BSV (p < 0.02) than in SOR, but this effect was blunted in rats given an angiotensin-converting enzyme inhibitor prior to BSV.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Subdiaphragmatic vagotomy in rats induces systemic hypertension and sodium retention. 129 60

It has been demonstrated in animal model of somatic pain that hypothalamic paraventricular nucleus (PVN) participates in acupuncture analgesia, probably by mediation of vasopressin release. The role of PVN in acupuncture analgesia for experimental visceral pain in rats was further investigated in the present study. Experimental results demonstrated that electroacupuncture could inhibit the writhing response, produced by intraperitoneal injection of antimonium potassium tartrate and this inhibitory effect could be enhanced by electrical stimulation of PVN, but decreased by electrolytical lesion of PVN, intracerebroventricular injection of vasopressin antiserum (14 microliters) or the vasopressin antagonist, d(CH2)5Tyr(Me)-AVP (500 ng/5 microliters). Intraperitoneal administration of the latter drug (10 micrograms/kg), however, was ineffective. The above experimental results suggest that vasopressinergic neurons in PVN also participate in the inhibition of visceral pain by electroacupuncture.
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PMID:[Involvement of vasopressinergic neurons of paraventricular nucleus in the electroacupuncture-induced inhibition of experimental visceral pain in rats]. 129 59

Two sets of new observations are reported: (i) astrocytes in primary cultures show an increased potassium-induced swelling in the presence of 1-100 x 10(-12) M vasopressin, whereas no similar phenomenon is found in primary cultures of neurons, and (ii) the furosemide-sensitive cotransport system for uptake of K+, Na+, and Cl-, which is known to exist in astrocytes, is absent in neurons. On the basis of these findings and observations by other investigators on transport of ions and water in the brain in vivo, a novel mechanism is suggested, according to which all boundaries of brain parenchymal tissue (perivascular astrocytic end-feet, glia limitans, and ependyma) in the absence of vasopressin are capable of performing a net uptake of K+, Na+, and Cl- without uptake of water, and that the resulting hyperosmolarity in the presence of vasopressin leads to water uptake (cell swelling), which causes a reduction in the amount of water in the interstitial fluid and thus an increase in extracellular concentrations of ions.
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PMID:Effect of vasopressin on brain swelling at the cellular level: do astrocytes exhibit a furosemide--vasopressin-sensitive mechanism for volume regulation? 129 87


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