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)

The development and evolution of hypertensive vascular lesions affecting the arterial supply of (a) the kidney and (b) organs other than the kidney were studied in rats developing either malignant (MHY) or benign (BHY) hypertension 3, 6, 9 and 12 days after aortic ligation between the renal arteries. Vascular disease evolved into two distinct patterns which suggested acute renal damage to be the determinant for the development of either the malignant or benign form of hypertension. Three days after aortic ligation MHY and BHY animals showed widespread fibrinoid deposition in vascular territories above the aortic ligature. However, in MHYs these lesions were much more severe and, in the kidney, they were accompanied by the development of focal parenchymal atrophy, microinfarcts and hyalin droplet degeneration of cells of the Bowman capsule. The degree of renal damage correlated with elevations in blood urea nitrogen (BUN) and plasma creatinine; however, there was no correlation with rises in blood pressure, plasma renin activity (PRA), aldosterone or corticosterone which were similarly elevated in 3-day MHY and 3-day BHY animals. Between 6 and 12 days a marked clearance of fibrinoid took place in all organ beds of BHYs, but in the non-renal vasculature of MHY animals fibrinoid remained prominent and served as the central core for necrotising arterial lesions. In the kidney of MHYs some reduction in the fibrinoid content was observed, but the parenchymal damage perpetuating from the earlier stages had exacerbated leading to collagen deposition and a marked increase in the collagen concentration of the renal cortex. These features were accompanied by further elevations in PRA and corticosteroids and a progressive deterioration of renal function. By contrast, in 12-day BHY animals, despite sustained hypertension, PRA and corticosteroids were falling from their previously higher levels and normal renal function was maintained. These studies warrant inference that extensive parenchymal damage of the kidney due in part to severe arterial fibrinoid deposition is one of the initial events in the development of malignant hypertension.
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PMID:Acute arterial fibrinoid deposition and ischaemic parenchymal damage of the kidney. Pathogenic factors in the development of malignant hypertension. 636 44

Urinary excretion of kallikrein (UKal), sodium, potassium, protein, and creatinine, as well as the kidney content of kallikrein and renin, was studied in spontaneously hypertensive FH/Wjd (FH) male and female rats and in age- and sex-matched normal Wistar rats. With the exception of 1-month-old rats UKal excretion was significantly lower in FH rats than in Wistar rats. FH females also excreted less UKal than Wistar females. No UKal inhibitor or increased degradation of this enzyme in the urine of FH rats was detected. There was no difference in creatinine clearance, blood urea nitrogen, or serum electrolytes, and calcium between 5-month-old FH and Wistar males. Wistar rat kidneys contained about twice as much kallikrein as FH rat kidneys. From the age of 2 months FH males excreted more sodium, as well as urine, than all other groups. No differences in potassium excretion were observed. Only FH males, 4 months and older, developed proteinuria. FH males and females became hypertensive at the ages of 2 and 4.5 months, respectively. Plasma renin activity, as well as renal renin activity, was significantly lower in FH than in Wistar males. In conclusion, the decrease in UKal activity which precedes the onset of hypertension suggests that the abnormality in the renal kallikrein system may be involved in the pathogenesis of hypertension in FH rats.
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PMID:Urinary and renal kallikrein in hypertensive fawn-hooded (FH/Wjd) rats. 636 17

In 7 splenectomized dogs a left renal vein-splenic vein anastomosis was performed and the right kidney removed. Eighteen to twenty-four months after portalization of renal venous blood no significant alterations of liver function tests were observed. Long-term diversion of renal venous blood into the liver was followed by a slight increase of creatinine and 25-OH-D, a decrease of alpha-amino acid nitrogen in blood plasma and of plasma renin activity in peripheral blood, by signs of slight carbohydrate intolerance despite hyperinsulinaemia, and a slight decrease of erythrocyte count. No influence of this procedure on plasma proteins, lipids, electrolytes, aldosterone and cortisol was found. No morphological abnormalities in the liver and kidney tissue were found.
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PMID:Metabolic effects of long-term diversion of renal venous blood into the portal system. 637 61

Nifedipine (10 mg qid) and captopril (25 mg qid) were tested alone and in combination in 14 patients suffering from severe primary hypertension. Each study period was of 1 week's duration. Circulatory response was evaluated through hourly pressure and pulse rate readings. The fall in pressure after oral nifedipine was maximal within 1 hr or less and was generally accompanied by palpitation and increase in pulse rate; with a six hourly dosing regimen the tendency of blood pressure to recover after each dose was interrupted by the next dose, so that values remained significantly reduced throughout the 24 hr, although pressure fluctuations were evident. Promptness of the antihypertensive action of captopril was similar, but the magnitude and the duration of the fall in pressure were less pronounced. When the converting-enzyme inhibitor was combined with the calcium-channel blocker, pressure fluctuations were not abolished, but the antihypertensive response was definitely enhanced, so that normal blood pressure was maintained for several hours during the day. Additional positive effects of captopril were mitigation of the heart rate reaction and prevention of the ankle pitting or edema elicited by nifedipine. A balance in arteriolar and venular dilatation promoted by captopril is the suggested mechanism for these effects. With the two-drug combination the function of the left ventricle was not reduced and possibly improved; blood urea nitrogen and serum electrolyte and creatinine concentration were not affected. Plasma renin activity increased with captopril and reverted toward baseline with the addition of nifedipine, suggesting an interference of the calcium-channel blocker with the release of renin.
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PMID:Calcium-channel blockade with nifedipine and angiotensin converting-enzyme inhibition with captopril in the therapy of patients with severe primary hypertension. 637 89

This study tested the ability of the converting enzyme inhibitor, captopril, to lessen the severity of acute renal failure following temporary occlusion of the renal artery. In the control group, 11 dogs were anesthetized with halothane, and the left kidney was isolated through a midline incision. The renal artery, vein, and ureter were then clamped for 120 min. Immediately after occlusion, the kidney was flushed with 40 ml of saline at 34 degrees C. When the clamp was released, a contralateral nephrectomy was performed and the animal allowed to recover. Serum creatinine and blood urea nitrogen levels were followed on a daily basis thereafter. Thirteen captopril-treated dogs were treated in the same fashion except that captopril (1.25 ml/kg, i.v.) was given prior to the 120-min period of renal ischemia. Three of 11 (27%) control dogs survived, whereas 10 of 13 (77%) captopril-treated animals survived (P less than 0.05). Serum creatinine (5.4 +/- 2.5 mg/dl) and serum urea nitrogen (96 +/- 33 mg/dl) peaked on day 8 in the captopril-treated group and were consistently lower than in the untreated group. These observations suggest that captopril is useful when temporary interruption of the renal circulation is encountered, such as in renal autotransplantation, cadaveric renal transplantation, and renal revascularization. These data also suggest that inhibition of the renin-angiotensin system may lessen the severity of acute renal failure following renal ischemia.
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PMID:Enhancement of recovery in postischemic acute renal failure with captopril. 637 20

Severe hyperkalemia developed in an 85-year-old man after he had been receiving piroxicam treatment for several months. At admission his serum potassium level was 9.3 mEq/L; total CO2 level, 11 mmole/L; chloride level, 122 mEq/L; serum urea nitrogen level, 54 mg/dL; and creatinine level, 2.5 mg/dL. Hyperkalemia resolved after withdrawal of the drug and polystyrene sodium sulfonate therapy and the nonanion gap acidosis subsided concomitantly. His serum urea nitrogen and creatinine levels remained unchanged. He had abnormally low plasma renin activity, which gradually returned to normal, and aldosterone concentration, which remained low. The nonsteroidal drug may have impaired renin secretion, adrenal responsiveness to angiotensin, or the action of aldosterone on the renal tubule.
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PMID:Severe hyperkalemia during piroxicam therapy. 650 49

The effects of 2 potassium-retaining diuretics on arterial pressure, intravascular volume, responses of the renin-angiotensin-aldosterone system, serum electrolytes, and renal function were compared by means of an 8-wk double-blind, crossover trial in 13 patients with "volume-dependent" essential hypertension. The fall in systolic, diastolic, and mean arterial pressures in the supine and erect positions (all p less than 0.005) induced by spironolactone was greater than that by triamterene. The pressure fall induced by spironolactone was also associated with a persistent contraction in plasma volume (p less than 0.05) and a secondary hyperaldosteronism that was not accompanied by hypokalemic alkalosis. The pressure fall induced by triamterene was not associated with reduced plasma volume, effect on plasma renin activity, or aldosterone excretion. Both drugs produced significant rises in blood urea nitrogen and creatinine levels that never exceeded normal limits.
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PMID:Spironolactone and triamterene in volume-dependent essential hypertension. 698 54

The present investigation was undertaken to find the differences, if any, in the pattern of nephrotoxic acute renal failure (HgCl2, 4.7 mg/kg body weight SC), in the developing rat and its relationship to the renin angiotensin system. No differences in renal cortical renin content were found between 2, 4, and 8 week olds, but plasma renin concentration was highest at 2 weeks and declined with age. Plasma renin was significantly increased in all groups 6 hr after HgCl2 injection, and the percentage of increase was highest in the 4 week olds. Despite these differences in initial plasma renin and in changes in plasma renin after HgCl2, the pattern of acute renal failure (as assessed by changes in blood urea nitrogen) was similar in the three groups for the first three days. Subsequently, the 4 and 8 week olds exhibited recovery (blood urea nitrogen began to decline), whereas blood urea nitrogen continued to increase to the fifth day in the 2 week olds. The mortality was highest in this group. No simple correlation was observed between basal renal renin, plasma renin, the increase in plasma renin following HgCl2 injection, and the pattern or severity of acute renal failure.
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PMID:HgCl2-induced acute renal failure in the developing rat. 699 81

These studies examined the effects of the volume expansion and the enhanced activity of the renin-angiotensin system during pregnancy on the severity of glycerol-induced myoglobinuric acute renal failure (ARF) in the rat. Renal cortical renin content (RCRC) and plasma renin concentration (PRC) were measured during the first, second, and third weeks of pregnancy. There were no significant changes in RCRC during pregnancy, but PRC was significantly elevated by the third week (22 +/- 2 vs. 12 +/- 2 ng angiotensin I/ml/k, p less than 0.001), despite plasma volume expansion as assessed by changes in the hemotocrit (37.7 +/- 0.5 vs. 46.4 +/- 0.6%, p less than 0.001). Despite the elevated PRC, a significant reduction in the severity of ARF was seen during the third week of pregnancy, as assessed by both blood urea nitrogen and inulin clearance measurements. When a sustained natriuresis was superimposed earlier in pregnancy by saline drinking, significantly more protection against ARF was seen, but with less plasma volume expansion. These results suggest that the mechanism by which saline drinking confers protection may be independent of the degree of volume expansion but may be dependent upon the associated sustained natriuresis.
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PMID:Glycerol-induced myohemoglobinuric acute renal failure in the pregnant rat. 699 72

In seven splenectomised dogs a left renal vein-splenic vein anastomosis was performed and the right kidney removed. Eighteen to twenty-four months after portalisation of renal venous blood no significant alterations of liver function tests were found. Long-term diversion of renal venous blood into the liver was followed by a slight increase of creatinine and 25(OH)D3, a decrease of alpha-amino acid nitrogen in blood plasma and of plasma renin activity in peripheral blood, by symptoms of slight carbohydrate intolerance despite hyperinsulinaemia and a slight decrease of erythrocytosis. No influence of this procedure on plasma proteins, lipids, electrolytes, aldosterone and cortisol was observed. No morphological abnormalities in liver and kidney tissues were found.
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PMID:Metabolic effects of long-term diversion of renal venous blood into the portal system. 701 1


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