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 emergence of diuretic drugs and angiotensin converting enzyme (ACE) inhibitors ranks amongst the major therapeutic advances of modern medicine. The discovery of these drug groups arose largely by chance, yet each has dramatically influenced the treatment of congestive cardiac failure and arterial hypertension. The central role which diuretics have had in the management of both oedema and hypertension hinges on their ability to induce a net renal excretion of solute and water by selective interference with either active or passive ion transport processes in different segments of the nephron. Irrespective of sites of action, the continued antihypertensive action of diuretics is characterized by a reduction in plasma volume and extracellular fluid (ECF) volume that lasts for as long as the diuretic is given. The mechanism of this effect remains unclear but may involve autoregulatory reactions that leave cardiac output unaltered but maintain a sustained reduction in total peripheral resistance. ACE inhibitors also lower blood pressure by decreasing total peripheral resistance, leaving cardiac output, plasma volume and ECF volume unchanged. The detailed way these haemodynamic changes are achieved remains unknown but inhibition of converting enzyme present not only in the kidney but also in many extrarenal tissue sites, appears important. In both hypertension and cardiac failure, however, the kidney acts as a key target organ for ACE inhibitors. The increased renal vascular resistance and inappropriate renal salt excretion are reversed with enhanced renal blood flow and saluresis. Both angiotensin II (AII) and vasopressin-mediated contraction of glomerular mesangial cells is inhibited, making glomerular filtration more efficient. Reduced aldosterone secondary to blockade of AII formation contributes to saluresis whilst encouraging positive potassium balance. ACE inhibition also impairs breakdown of kinins which may contribute to intrarenal and peripheral vasodilation either on their own or via release of prostaglandins and other vasoactive substances. The hypotensive actions of diuretics are potentiated by ACE inhibition primarily through blockade of AII formation and prevention of secondary aldosteronism. In combination, these drugs permit low doses to be used because of their synergistic effects. Caution has to be exercised whenever ACE inhibition is used, without and especially with diuretics, in the management of renovascular hypertension and other low-perfusion states. In these circumstances, AII plays an important autoregulatory role in preserving glomerular filtration through an increase in post-glomerular resistance.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Evolution of diuretics and ACE inhibitors, their renal and antihypertensive actions--parallels and contrasts. 303 17

Inhibition of the angiotensin converting enzyme (ACE) is associated with a decrease in renal vascular resistance, an increase in renal blood flow and a redistribution of intrarenal blood flow toward juxtamedullary nephrons. In general, ACE-inhibition does not affect normal glomerular filtration rate (GFR) but may increase GFR in patients on a low sodium intake prior to treatment. Since the rise in GFR is smaller than the rise in renal blood flow, in most instances a decrease in filtration fraction will result. In contrast to other vasodilator drugs, the decrease in blood pressure induced by ACE-inhibition is not accompanied by sodium retention, but rather by an initial natriuresis. ACE-inhibition also prevents secondary aldosteronism and thereby avoids renal potassium loss. The initial positive potassium balance after ACE-inhibition may protect patients with heart disease from potentially hazardous arrhythmias. Redistribution of intrarenal blood flow with increased medullary flow, in addition, will antagonize the hydrosmotic effect of vasopressin and thus result in a rise in free-water clearance. Finally, based on experimental evidence, long-term treatment with ACE-inhibitors may have a protective effect on renal function by reducing glomerular filtration pressure.
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PMID:[Inhibition of the angiotensin-converting enzyme--effect on kidney function and electrolyte balance]. 306 59

The long-term results of surgical and specific drug therapy were compared in a group of 57 patients with primary aldosteronism (PA) (46 with aldosterone-producing adenoma (APA), 11 with idiopathic hyperaldosteronism (IHA) and bilateral adrenal hyperplasia). Unilateral adrenalectomy completely normalized blood pressure (BP) in 77.1% of surgically treated APA, evidently improving hypertension in remaining 22.9%. No recurrence of the adenoma in the remaining adrenal was seen in any of the surgical APA cases. In 19 of the non-surgical patients (11 with APA, 8 with IHA) monotherapy with spironolactone reduced blood pressure in 73%, though total BP normalization was an exception. The treatment normalized hypokalemia, low total exchangeable potassium, tendency to hypernatremia, and high total exchangeable sodium. Surgical as well as conservative therapy increased to normal or above-normal levels plasma renin activity suppressed prior to treatment. Pre-operatively high urine and plasma aldosterone levels normalized in all adrenalectomized patients, but remained above the normal range during spironolactone therapy in spite of a small decline in its absolute values. The disturbances of maximum renal concentrating capacity due to impaired nephron responsiveness to sufficiently high endogenous vasopressin concentrations were completely eliminated after kaliopenic nephropathy had been repaired. The other renal functions remained within normal values. Echocardiographically diagnosed left ventricular hypertrophy was seen less often than in the other types of arterial hypertension, tending to regress after APA management. Our longitudinal study (2-16 years) showed primary aldosteronism as a well curable, albeit rare, cause of hypertension. As regards BP and laboratory tests normalization, better results were achieved in surgical APA cases than in patients treated with spironolactone. Older age, longer history of hypertension and more frequent incidence of obesity, nephrosclerosis and pyelonephritis may be responsible for hypertension persisting after surgical treatment.
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PMID:Long-term results of surgical and conservative treatment of patients with primary aldosteronism. 345 May 33

The purpose of this study was to investigate the main renal and hormonal responses to head-down bed rest, which is currently considered a reliable experimental model for the simulation of weightlessness. Urinary output and electrolytes, plasma renin activity (PRA), aldosterone (PA), antidiuretic hormone (ADH) and immunoreactive neurophysin-I (Np) were measured in eight adult volunteers submitted to a 4-day head-down bed rest (-6 degrees) after a 24-h control period in the horizontal position (day 0). Four of the eight subjects were submitted to two 1-h periods of controlled muscular exercise (50% VO2max) from day 1 to day 4. Throughout the head-down bed rest period, urinary output remained stable, although lower than in the control period (day 0), but the urinary Na/K ratio decreased. Plasma electrolytes and osmolality, and creatinine clearance remained unchanged. There was no significant difference between exercising and non-exercising subjects. At the hormonal level, PRA and PA increased during the head-down bed rest. This increase was more pronounced in the group with exercise. At the end of the tilt period, PRA and PA were about 3 times higher than on day 1. No significant changes could be observed for ADH and Np. It is concluded that a 4-day head-down bed rest results in no apparent changes in neurohypophyseal secretory activity, and in a progressive secondary hyperaldosteronism.
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PMID:Plasma vasopressin, neurophysin, renin and aldosterone during a 4-day head-down bed rest with and without exercise. 351 79

The vasoconstrictor and vasopressor actions of vasopressin have been revealed in recent research through the use of highly specific and sensitive radioimmunoassays, employment of peptide antagonists, and comparison with an animal model which has hereditary absence of this hormone, the Brattleboro rat. Factors now known to modify the pressor effect of vasopressin are the baroreflexes, local vascular prostaglandin production, and a specific interaction with angiotensin II. In experimental models the volume retaining, but not the vasoconstrictor effect of vasopressin is necessary for mineralocorticoid-salt hypertension. Vasopressin contributes directly to the increase in arterial pressure of glycerol induced acute renal failure. In nephrectomized rats, plasma vasopressin is elevated and contributes directly to maintenance of pressure. Vasopressin antagonism may reduce arterial pressure in Goldblatt 1 and 2 kidney hypertension and in one genetic model, spontaneously hypertensive rat (SHR), but the peptide is not necessary for hypertension in these models. Plasma vasopressin is reduced in primary aldosteronism, but may be elevated in malignant hypertension. In essential hypertension, there is considerable disagreement among various studies in which plasma vasopressin, urine vasopressin excretion, platelet associated vasopressin, or vasopressin-neurophysin were measured as to whether there is evidence for increased secretion of vasopressin. Only preliminary studies of vasopressin antagonism in clinical hypertension have been reported. At present, there is no conclusive evidence that elevated vasopressin secretion occurs or is necessary for any form of clinical hypertension.
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PMID:The role of vasopressin in experimental and clinical hypertension. 388 2

In order to investigate the antidiuretic hormone (ADH) in essential hypertension and secondary hypertension, plasma ADH levels were measured in normal subjects, in patients with normal and low essential hypertension, and in other patients with various forms of secondary hypertension. Plasma ADH levels were significantly lower in low renin essential hypertension and higher in malignant hypertension than in normal subjects. The plasma ADH levels tended to be lower in renal hypertension and primary aldosteronism, and higher in renovascular hypertension, but these differences were not statistically significant. From these results, it appeared that ADH might play a role in malignant hypertension, but not in the other hypertensive diseases.
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PMID:Plasma antidiuretic hormone levels in patients with normal and low renin essential hypertension, and secondary hypertension. 636 8

Historically, the sodium ion has been given prominence in relation to cardiovascular disease, perhaps to the exclusion of other ions. Recently, other ions, including chloride, potassium, magnesium and calcium have received increasing attention in relation to hypertension, cardiac arrhythmias, and metabolic derangements. Endocrine factors controlling these ions have also received increasing attention; they include classic hormonal actions as well as neurotransmission and paracrine hormonal actions. Studies indicate that control of the renin-angiotensin-aldosterone system resides in cytosolic calcium ion levels in the juxtaglomerular cell, as well as chloride ion and prostaglandins at the macula densa. Renin release is stimulated by hyperpolarisation of the juxtaglomerular cell induced by beta 1-agonists, parathyroid hormone, glucagon, magnesium and low cytosol calcium. Renin release is inhibited by high calcium, potassium and angiotensin II. Subsequent to renin release, hormonal regulation includes stimulation of converting enzyme activity by cortisol and prostaglandin (PGE2). Other hormonal control includes antidiuretic hormone producing dilution of extracellular electrolytes and augmented peripheral resistance. A recently identified natriuretic factor isolated from cardiac atria appears to be a potent diuretic with actions similar to that of frusemide (furosemide). Other electrolytes have received closer scrutiny. Chloride may play a dominant role in renal sodium reabsorption, responding to prostaglandin levels. Calcium has been recognised as a basic regulator of the secretion of such hormones as noradrenaline, renin, and aldosterone. As well, calcium ion changes are the means by which smooth muscle contraction is effected. Parathyroid hormone and vitamin D regulate the level of this ion in the body. In addition, a high dietary calcium intake appears to play a protective role against hypertension, while calcium channel blockers appear to reduce blood pressure. Endocrine systems play a major role in the protection against acute elevations in serum potassium by means of insulin action and adrenergic modulation of extrarenal potassium disposal. Aldosterone is recognised as the delayed regulator of potassium excretion. Magnesium levels fall in hyperaldosteronism, hyperparathyroidism, and diabetic keto-acidosis, as well as in malnutrition states. A coexisting potassium deficiency may be refractory to therapy until hypomagnesaemia is corrected. The integrated action of these hormones and electrolytes are thus of major importance in regulation of the cardiovascular system.
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PMID:Endocrine physiology of electrolyte metabolism. 638 78

Plasma concentration (PAVP) and urinary excretion (UAVP) of arginine-vasopressin were studied in 8 patients with primary aldosteronism (PA) during a 36 hour period of fluid restriction in relation to the disturbances of their maximal renal concentrating capacity. The results in untreated patients suffering from PA were compared with the findings in patients after a successful treatment of PA as well as with the results in 9 control subjects. The reduction of maximal renal concentrating ability in PA before the treatment was accompanied with a high excretion of UAVP and the physiological reaction of PAVP to dehydration. Together with the shift of the regression line of the dependence of UOsm on UAVP to higher values of UAVP this indicates a decrease of the sensitivity of the nephrons to the sufficiently high concentrations of endogenous AVP. The increase of renal AVP clearance in PA participates in the high urinary excretion of AVP. The disturbance of the renal concentrating ability as well as the changes of urinary AVP in PA are mostly reversible. After the successful treatment of PA and the completion of potassium stores in the body as well as the healing of the kaliopenic nephropathy, the maximal renal concentrating capacity and AVP gradually return to values close or equal to those in healthy subjects.
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PMID:Plasma concentration and urinary excretion of arginine-vasopressin in primary aldosteronism during the fluid deprivation tests. 668 50

The pathogenesis of edema and hyponatremia associated with chronic obstructive lung disease (COLD) is poorly understood. In ten edematous COLD patients with acute respiratory failure (ARF), we monitored plasma renin activity (PRA), aldosterone (PA), and antidiuretic hormone (arginine vasopressin, AVP) for six days. Six patients receiving supplemental oxygen and antibiotics had near normal PRA, PA, and AVP, and diuresed Na+ and H2O and lost weight; only one patient was hyponatremic (PNa+ less than 130 mEq/L). On the same therapy, nonresponders (n = 4), with persistently elevated PRA, PA, and AVP, demonstrated no loss of Na+, H2O, or weight; three patients were hyponatremic. The PRA and PA correlated inversely with sodium loss; AVP correlated inversely with free water clearance. These studies suggest that in patients with COLD, edema, and ARF (1) lack of sodium diuresis may be contributed to by secondary hyperaldosteronism; and (2) hyponatremia can be explained by inappropriately elevated plasma AVP.
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PMID:Hormonal abnormalities affecting sodium and water balance in acute respiratory failure due to chronic obstructive lung disease. 669 Feb 51

Idiopathic edema is a little studied syndrome occurring in middle-aged women. Edemas are not associated with cardiac, liver or kidney pathology and are frequently caused by psychic trauma, infection or pregnancy. The disease pathogenesis is stipulated by hyperaldosteronism, antidiuretic hormone excess, estrogen-progesterone unbalance, initial disorder of the central hypothalamic regulation, etc. The treatment is mainly symptomatic; the disease course is non-malignant.
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PMID:[Diagnosis and treatment of the idiopathic edema syndrome]. 743 37


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