Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.23.15 (renin)
 35,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A study was made of the blood plasma renin activity in 63 patients suffering from thyrotoxicosis before the treatment and in 42 healthy individuals. In comparison with the healthy, renin activity was increased in patients with thyrotoxicosis and displayed a positive correlation with the severity of the disease the level of protein-bound iodine, tachycardia and the degree of loss of weight. Stimulation of the renin-angiotensin system by the salt-free diet, hydrochlorthiazide and by placing the body into orthostatic position caused a relatively weaker increase in the renin activity in comparison with such in healthy individuals. Following successful treatment and the occurrence of an euthyroidal state renin activity proved to fall to the normal level. An increased renin activity was combined with increased urinary aldosterone excretion with a normal serum electrolyte level. Such combination pointed to the secondary character of aldosteronism. Block of the alpha- and beta-adrenergic receptors led to reduction in the level of renin activity. Despite the frequent affection of hepatic function there was revealed no correlation between the increase in the renin activity and the pathological results of hepatic tests. Plasma renin activity was reduced in 8 patients with myxedema. It is supposed that the principal factors causing activation of the renin-angiotensin system in thyrotoxicosis were the loss of water and electrolytes by the organism and the appearance of oversensitivity to adrenergic receptors.
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PMID:[State of the renin-angiotensin system in thyrotoxicosis]. 4 92

The effect of propranolol has been studied in two patients with chronic renal failure and hypertension which remained refractory despite the removal of excess sodium and water by dialysis. Measurements of plasma-renin, exchangeable sodium, and blood-volume demonstrated that in both patients hypertension was due to excess renin. The administration of propranolol was followed by a rapid fall in blood-pressure to normal, thereby obviating the need for bilateral nephrectomy. In both patients the fall in blood-pressure was accompanied by a striking fall in plasma-renin, and in one there was a highly significant association between plasma-renin activity and mean arterial pressure.
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PMID:Effect of beta-adrenergic blockade on plasma-renin activity and intractable hypertension in patients receiving regular dialysis treatment. 5 51

Ten women with "idiopathic" edema had sodium and water retention and a rapid gain in weight when their accustomed intake of diuretics was suddenly stopped. The magnitude of these changes was directly related to the levels of plasma-rening activity before withdrawal of diuretics. Nine patients became edematous. Within 10 days of stopping diuretics, plasma-renin activity and urinary aldosterone excretion decreased to normal or below and within 20 days weight-gain and edema had subsided in seven patients. But the greatest gains in weight, in three patients, were sustained beyond 20 days. Nevertheless, a year later, two of these three patients were free of edema without the use of diuretics. Intermittent edema of unknown cause in most, if not all, otherwise healthy women seems to result from their use of diuretics, abetted in some patients by self-imposed flucuation of sodium and carbohydrate intake, and does not appear to be idiopathic.
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PMID:Is "idiopathic" edema idiopathic? 8 58

When renal function is compromised, the circulation to the kidney is sustained by a major prostaglandin component, withdrawal of which results in significant hemodynamic effects, particularly reduction in blood flow to the inner cortex and medulla. Prostaglandins modulate the effects of vasoactive hormones by attenuating the renal actions of the renin-angiotensin system and contributing to and, perhaps, mediating some of those of the kallikreinkinin system. In addition, a prostaglandin mechanism, presumably located in the renal arterioles, participates in the regulation of renin release. Although cyclooxygenase is present in several renal tissues, the major products of arachidonic acid metabolism may be tissue specific and, consequently, their effects may be primarily restricted to one compartment, e.g., the proposed interaction of prostacyclin and renin within the vascular pole of the glomerulus; and PGE2/PGF2a with the kallikrein-kinin system within the urinary compartment. The former is related to the regulation of renin release and renal vascular resistance and the latter to the excretion of water and perhaps salt.
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PMID:Compartmentalization of prostaglandins and prostacyclin within the kidney: implications for renal function. 10 56

In eight patients who had received long-term parenteral nutrition because of short-bowel syndrome the need for parenteral supply of fluid, sodium, and potassium was estimated by balance studies. Six patients had jejunostomies. In two, most of the colon was preserved. Jejunostomy patients had a huge stool mass (1710--5270 g, median 2530 g/day) with fixed concentrations of sodium (92 +/- 10 mmol/l) and potassium (15 +/- 4 mmol/l). In contrast, two patients with massive small-bowel resection but with more than half of the colon intact showed almost normal sodium absorption and considerably smaller stool mass (170--510 g/day). Despite apparently good health and normal plasma electrolytes, urea, and haematocrit, four of six jejunostomy patients were sodium-depleted with low plasma volume, low sodium excretion in the urine, and increased plasma renin activity and, in the three most severe cases, increased aldosterone. Even in case of sodium depletion the sodium loss from jejunostomy effluents remained high and presumably unaffected by salt-retaining hormones. The study confirms the importance of preservation of part of the colon for maintenance of fluid and electrolyte balance in patients with extensive bowel resection. Jejunostomy patients who are eating normally may need large parenteral saline supply. Assessment of water and electrolyte homeostasis in these patients requires determination of the urinary sodium excretion and is supported by measurements of plasma renin activity and plasma aldosterone concentration.
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PMID:Fluid and electrolyte absorption and renin-angiotensin-aldosterone axis in patients with severe short-bowel syndrome. 11 6

The effects of propranolol (l mg/kg/H infused in the renal artery) on the diuretic action of furosemide (20 mg/kg i.v.) have been studied in pentobarbital anesthetized dogs. We obtained the 3 following results : the urine remained isotonic to the plasma during the 6 hours following the furosemide injection ; the urinary output of sodium and water, measured during 6 hours after furosemide injection, was increased ; the renin hypersecretion was inhibited.
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PMID:[Effect of d-1 propranolol on urinary osmolarity after furosemide in anesthesized dog]. 13 38

In this chapter we have emphasized especially the intrinsic controls of the circulation, such as the autoregulation mechanism for control of local blood flow, automatic control of cardiac output, long-term control of arterial pressure, long-term control of blood volume, and automatic distribution of fluids between the circulation and the interstitial spaces. The reasons for emphasizing these mechanisms are several: first, many experiments have now shown that the intrinsic mechanisms can provide highly stable long-term control of the circulation. Second, the value of the nervous and hormonal controls have probably been greatly overemphasized in the past. And, third, there are special complexities of the intrinsic controls--such as nonlinearities, delay in responses, and other effects--that have made these difficult to understand; it is probably these difficulties that have led to their underemphasis. However, we have not meant to take from the nervous and hormonal systems their true importance in circulatory control. For instance, intrinsic mechanisms have almost no capability for acute arterial pressure control (only for long-term control), and they have no mechanism for providing the drive necessary to make the animal ingest water and electrolytes. These require the nervous controls. Also, nervous reflexes are important in enhancing the effectiveness of blood volume control and control of cardiac pumping. Among the hormonal mechanisms, the renin-angiotensin system can provide a modest degree of arterial pressure control when the pressure falls below normal by eliciting a vasoconstrictor response in the peripheral blood vessels. However, this system seems to have an even more important renal function, a direct effect on kidneys to cause fluid retention; this in turn increases the body fluid volume and in this way increases the arterial pressure. Finally, the roles of ADH and aldosterone in the control of blood volume have probably been greatly overemphasized. On the other hand, both clinical experience and experimental studies are beginning to demonstrate that the thirst/ADH system is probably by far the most potent mechanism that we have for control of extracellular fluid sodium ion concentration. On the other hand, the aldosterone mechanism seems to be our primary control system for maintaining a normal extracellular fluid concentration of potassium.
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PMID:Integration and control of circulatory function. 13 39

The effect of dl-sotalol (intrarenal perfusion of 19 mg/kg during 30 min) on urinary concentration was studied under pentobarbital anaesthesia in dehydrated dogs. Sotalol infusion decreased urinary osmolality and increased natriuresis and urine flow. This diuretic action was accompanied by the reduction of the renin hypersecretion elicited by water deprivation.
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PMID:[The effects of dl-sotalol on the urinary osmolarity of anesthetized dogs]. 13 72

Biochemical (myocardial DNA, RNA, and hydroxyproline) and humoral (plasma [PRA] and kidney [KRA] renin activity) factors were determined in spontaneously hypertensive rats (SHR) and normotensive Wistar controls (NR) before and following treatment with minoxidil or propranolol. Minoxidil (150 mg.litre-1 drinking water) effectively controlled blood pressure (17.3 kPa vs 24.9 kPa [130 mmHg vs 187 mmHg], P less than 0.001) despite marked and sustained increases in both PRA and KRA ventricular weight which were not reduced and myocardial DNA, RNA, and hyperdroxyproline which were increased by minoxidil (P less than 0.01). In contrast propranolol did not reduce blood pressure in SHR but ventricular weight was reduced somewhat (3.1 +/- 0.4 mg.g-1 vs 3.4 +/- 0.09 mg.g-1, P less than 0.05); in both SHR and NR, KRA, and PRA were lowered by pranolol. Methyldopa which controlled blood pressure and lowered PRA led to a reversal of hypertrophy. Thus, although blood pressure control is obviously important for reversing cardiac hypertrophy, it may not be the sole factor for the development and reversal of cardiac hypertrophy.
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PMID:Cardiac hypertrophy and antihypertensive therapy. 14 19

Circadian rhythms in urinary water, sodium, potassium and proteins excretion are studied in 45 rats living alone in metabolism cages. Urines are collected during 4 consecutive 6 hours long periods during 2 consecutive days. Large circadian variations of these parameters (especially water and proteins excretion and urinary protein concentration) are described. The influence of feeding rhythms on the circadian urinary excretion rhythms is discussed. It is proposed that nightly renal hemodynamic changes (during meal digestion or with high renin plasma levels) can induce modifications in glomerular filtration rate and electrolytes and macromolecules transglomerular flow.
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PMID:[Circadian rhythmus of the excretion of electrolytes and urinary proteins in rats]. 15 Aug 80


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