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)

1. In pentobarbitone-anaesthetized dogs, prazosin (2 x 1-3 micronmol day-1 kg-1; 2 x 0-5 mg day-1 kg-1) administered orally for 3 days reduced resting aortic blood pressure as well as the pressor response to bilateral carotid occlusion. Prazosin neither affected resting heart rate nor the tachycardia induced by intravenous isoprenaline, noradrenaline and electrical stimulation of preganglionic and postganglionic sympathetic nerve fibres. Prazosin significantly attenuated the fall in perfusion pressure in a perfused hind leg resulting from the section of the ipsilateral sympathetic lumbar chain. Furthermore, the drug inhibited by about 50% the hind-leg pressor responses elicited by intra-arterial administration of alpha-adrenoreceptor agonists and by stimulation of the lumbar sympathetic chain, without altering the effects of angiotension II. 2. Acute administration of prazosin into the innervated hind leg provoked a dose-related reduction in vascular resistance. However, after spinal anaesthesia no such an effect was observed even when vascular tone was increased by infusion of vasopressin. Under the same experimental conditions administration of papaverine induced a vasodilatation. 3. This study confirms that prazosin impairs the function of vascular alpha-adrenoreceptors, and strongly challenges the claim that this compound produces a directly mediated vasodilatation of the leg vascular bed.
Clin Sci Mol Med Suppl 1976 Dec
PMID:Cardiovascular effects of prazosin in dogs. 107 89

1. The rate of renal excretion of arginine-vasopressin was determined during unrestricted fluid intake for 24 h and in response to fluid deprivation for 18 h in nine young men with very mild essential hypertension and compared with that in sixteen normotensive men of similar age. 2. Despite an equivalent osmolar stimulus, excretion of arginine-vasopressin was significantly greater in the reference group than in the reference group. This difference increased progressively with increasing dehydration. 3. We suggest that these findings are mainly due to an increased rate of secretion of arginine-vasopressin in response to mild hydropenia in hypertensive patients and that a moderate increase of release of arginine-vasopressin during periods of fluid deprivation may exert vascular effects and thus influence the perpetuation of hypertension.
Clin Sci Mol Med Suppl 1976 Dec
PMID:Increased renal excretion of arginine-vasopressin during mild hydropenia in young men with mild essential benign hypertension. 107 11

Dissatisfaction with the high morbidity and mortality of traditional methods of handling massive gastrointestinal hemorrhage has led to the exploration of means other than surgical to attain hemostasis. Some, such as selective arterial infusion of surgical Pituitrin, have quickly won general acceptance in hospitals where facilities and interested personnel are available. Others, such as alkalinization, have become popular because of their inherent simplicity. Systemic hypothermia, requiring intensive patient care, has not been without considerable risk of significant complications. Iced saline lavage has never been subjected to critical evaluation. It is possible that the emptying of the stomach through mechanical destruction of the intragastric clot by repeated irrigations, reducing the antral stimulation by relief of distension, may be as important as the temperature of the solution in the stomach. Gastric irrigations with norepinephrine solutions have awaited the results of physiologic studies showing that the cardiovascular and renal effects of injected levarterenol are avoided, and that permanent damage to the gastrointestinal mucosa does not result. Trials have been confined largely to very poor-risk patients, and the hemostasis that has resulted has not been explainable, in all cases, on the basis of the physiologic activity of the agent (e.g., control of bleeding from tumor vessels). Evacuation of gastric content prior to introduction of the norepinephrine solution seems important. Lower gastrointestinal bleeding from benign disease has also responded to advances in applied pharmacology, with intra-arterial infusion of surgical Pituitrin again coming into progressively wider use. Intraperitoneal instillation of norepinephrine has also proved useful, even in patients who have adhesions from prior surgery or inflammatory disease, but closer monitoring of blood pressure and urine output are necessary because some of this solution is absorbed by the parietal peritoneum and not deactivated by the liver before entering the systemic circulation. Taken together, selective arterial infusion of vasopressin and topical application of norepinephrine can be considered complementary rather than competitive therapies. Because of the more extensive experience with selective angiographic infusion, it should be the first choice in institutions where it is readily available. For patients in whom arterial puncture is inadvisable, and where angiography is not readily available, topically applied norepinephrine becomes the treatment of preference. We have demonstrated effectiveness of intraperitoneal norepinephrine in a patient in whom selective arterial infusion of surgical Pituitrin had failed. And the reverse would probably also hold true on occasion. Pharmacologic techniques represent a therapeutic advance, reducing the frequency with which surgical intervention becomes mandatory. But they are not a substitute for surgery...
Compr Ther 1975 Dec
PMID:Massive gastrointestinal hemorrhage. 108 29

The mechanism whereby an increase in left atrial pressure (LAP) causes a water diuresis in the anesthetized dog remains controversial. In the present study LAP was increased by inflation of an atrial balloon in two groups of animals. In the first group of eight intact dogs, mean LAP was increased from 3.4 to 17.6 mm Hg (P less than 0.001). The rise in LAP was associated with a mean increase in urine flow (V) from 0.70 to 1.29 ml/min (P less than 0.001), a decrease in urinary osmolality (Uosm) from 808 to 490 mOsm/kg of H2O (P less than 0.001) and an increase in free water clearance (CH2O) from -0.684 to -0.200 ml/min (P less than 0.025). This diuresis was associated with a mean decrease in antidiuretic hormone concentrations in plasma as measured by radioimmunoassay from 27.6 to 12.3 pg/ml (P less than 0.02). The changes in the urinary indexes and in the antidiuretic hormone concentrations were reversible and returned to control levels when the LAP was allowed to return to normal. A second group of dogs was acutely hypophysectomized, steroid replaced and given a constant infusion of vasopressin. In these animals, mean LAP was increased from 3.0 to 16.0 mm Hg (P less than 0.001) but no significant change in V (0.49 to 0.56 ml/min), Uosm (878 to 845 mOsm/kg of H2O) or CH2O (-0.750 to -0.620 ml/min) occurred. Cardiac output, renal arterial pressure, glomerular filtration rate and solute excretion were comparable in the two groups. We therefore conclude that suppression of antidiuretic hormone release is the primary mechanism whereby increased LAP causes a water diuresis in the anesthetized dog.
Kidney Int 1975 Dec
PMID:Mechanism of diuretic response to increased left atrial pressure in the anesthetized dog. 110 39

Acute and chronic effects on the fluid balance of radio-frequency forebrain lesions were studied in the goat. Medial lesions which involved practically the entire anterior wall of the third cerebral ventricle cause persistent loss of thirst and lack of significant antidiuretic hormone (ADH) release in response to hypernatraemia and plasma hyperosmolality. As acute response to such lesions an uncompensated, temporary water diuresis was seen, which rapidly caused pronounced hypernatraemia and hypovolaemia. Lesions extending laterally to encroach upon the supraoptic nuclei resulted in persistent signs of weak, inappropriate ADH secretion (=impaired water diuresis, renal salt wasting, and pronounced hyponatraemia during hydration). Forebrain damage, mainly restricted to the septal region, caused hyperdipsia. In some goats, obvious post-lesioning increase in salt appetite was observed which could not be coreelated to the extent of their forebrain damage. The results are discussed in relation to hypothalamic syndromes in man and previous studies on central control of fluid balance in the goat.
Brain Res 1975 Dec 05
PMID:Perturbations in fluid balance induced by medially placed forebrain lesions. 118 46

Nineteen patients with the Mallory-Weiss lesion diagnosed by panendoscopy are presented. This represents 10.5% of 180 acute upper-gastrointestinal bleeders. Only 36.8% of these 19 patients had a history of heavy ethanol intake and 26% had hiatus hernias. In addition to the Mallory-Weiss lesion, abnormalities in 63% were noted on endoscopy. None of the patients required surgery for control of the bleeding. Two patients were treated with selective arterial-vasopressin infusion. The importance of a high index of suspicion for this lesion in spite of the lack of a classical alcoholic or recurrent retching history and the value of intensive medical therapy, including early panendoscopy, is emphasized.
Am J Dig Dis 1975 Dec
PMID:Mallory-Weiss syndrome in perspective. 120 8

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.
Clin Sci Mol Med 1975 Dec
PMID:Potassium depletion induced by vasopressin and overhydration in the rabbit. 120 83

1. The effects of unilateral nephrectomy on urinary concentration and dilution were studied in Sprague-Dawley rats. To exclude incomplete suppression of antidiuretic hormone, free water formation was also sutdied in rats with congenital diabetes insipidus (Brattleboro strain). 2. Urinary solute-free water formation was similar in Sprague-Dawley and Brattleboro rats. Uninephrectomized animals excreted a water load promptly and diluted their urine to the same degree as control rats. Maximal values for Cwater and TCwater per kidney were higher after nephrectomy, but were similar to those of control rats at comparable rates of fluid delivery to the distal nephron. Renal tissue osmolaity was similar in uninephrectomized and sham-operated animals, indicating that nonantidiuretic hormone-dependent backflux of filtrate was the same in the two groups. The only defect observed in uninephrectomized animals was a small reduction in maximal urine osmolaity. 3. These results demonstrate that free water formation and reabsorption are unaffected by unilateral nephrectomy and suggest that, in the remaining kidney, filtrate reabsorption along the entire nephron increases in proportion to the increment in glomerular filtration.
Clin Sci Mol Med 1975 Dec
PMID:Urinary concentration and dilution after unilateral nephrectomy in the rat. 120 87

Nicotine stimulation, induced by cigarette smoking, has previously been identified as a potent stimulus for vasopressin release in humans. In this study, radioimmunoassay measurements of plasma vasopressin and human neurophysin were performed on samples taken from 14 normal subjects during cigarette smoking. Significant rises in vasopressin occurred in 10 of the 14 subjects and the same 10 had significant rises in neurophysin. Pretreatment with ethanol in 3 subjects either eliminated or greatly blunted the responses of both vasopressin and neurophysin to cigarette smoking. These studies indicate that the release mechanisms for vasopressin and neurophysin are closely linked in humans.
J Clin Endocrinol Metab 1975 Dec
PMID:Nicotine-stimulated release of neurophysin and vasopressin in humans. 120 97

Left atrial pacing was performed in three groups of anesthetized dogs. In the first group of eight intact dogs a mean increase in atrial rate (AR) from 140 +/- 7 to 244 +/- 6 was associated with a decrease in urinary osmolality (U osmol) from 631 +/- 72 to 264 +/- 43 mosmol/kg (P less than .001), and free-water clearance (CH20) increased from -.325 +/- .06 to +.355 +/- .15 ml/min (P less than .001). At the same time left atrial pressure (LAP) increased from 6 +/- 1 to 15 +/- 1 mmHg (P less than .001). A second group of studies was performed in six hypophysectomized, steroid-replaced animals receiving 40-50 muU/kg per min of antidiuretic hormone (ADH). In these animals AR was increased from 148 +/- 17 to 250 +/- 17 but diuresis did not occur. In these studies Uosmol was 690 +/- 55 before and 704 +/- 49 mosmol/kg after atrial pacing and CH20 also did not change. Left atrial pressure increased from 10 +/- 2 to 19 +/- 2 mmHg during atrial pacing. A third group of studies was performed in five animals with bilateral cervical vagotomy. In these animals AR was increased from 159 +/- 6 to 258 +/- 17 and LAP increased from 7 +/- 1 to 16 +/- 2 mmHg. Osmolality increased from 808 +/- 72 to 1,049 +/- 65 musmol/kg (P less than .005) and CH20 was unchanged. These results, therefore, indicate that atrial tachycardia primarily increases renal water excretion by suppressing ADH release. This reflex is dependent on the integrity of cervical vagal pathways.
Am J Physiol 1975 Dec
PMID:Mechanism of diuretic response associated with atrial tachycardia. 121 81


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