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)

Marked reduction of the monoaminergic nerve fluorescence and catecholamine tissue content were demonstrated in the ischemic kidney of rats made hypertensive by unilateral renal artery stenosis (two-kidney Goldblatt hypertension). The nonischemic kidney showed a normal degree of fluorescence and catecholamine content. The electron microscope failed to demonstrate recognizable nerves around most of the glomerular arterioles of the ischemic kidney, whereas a normal rich innervation was observed in the nonischemic side. The juxtaglomerular index and renal renin content were elevated in the ischemic kidney and markedly reduced in the nonischemic kidney. Juxtaglomerular cells were present in the glomerular mesangium and ultrastructurally showed changes consistent with increased renin synthesis. The extent of disruption of the sympathetic system in renal hypertension might play a role in the degree of hypersecretory response of the juxtaglomerular cells to renal artery constriction.
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PMID:The renal sympathetic system and juxtaglomerular cells in experimental renovascular hypertension. 99 66

Renin activities were determined in plasma and in single, microdissected juxtaglomerular apparatus in 19 patients with unilateral renal artery stenosis. The mean juxtaglomerular apparatus renin concentration in the stenosed kidneys was 5.5 +/- 1.2 (SEM) mug.l-1.h-1 which is about ten times that of the suppressed renin concentration in the contralateral kidneys (0.6 +/- 0.05 mug.l-1.h-1). On the affected side a positive correlation was found between intrarenal and renal venous renin concentration (r = 0.93; p less than 0.001). Both intrarenal and renal venous renin concentrations of the stenosed kindeys were positively correlated to renin secretion rates, as calculated from renin analysis in plasma from the vena cava and renal veins. No relationship could be demonstrated between intrarenal or renal venous renin concentration and the degree of blood pressure elevation or transstenotic pressure gradient. However, a positive correlation was evident between peripheral plasma renin activity and diastolic blood pressure (r = 0.88; p less than 0.001). Comparative enzyme kinetic analyses of renin from the juxtaglomerular apparatus and renal venous plasma were performed using sheep substrate. The lowest apparent Km-values of renin were found in renal venous plasma from the stenosed kidneys (198 +/- 13 mug/l) compared with the contralateral side (301 +/- 20 mug/l; p less than 0.001). Mean apparent Km-values of juxtaglomerular apparatus renin in the stenosed (270 +/- 36 mug/l) and contralateral (292 +/- 37 mug/l) kidneys did not differ. No significant differences were found between mean apparent Km-values for renin in peripheral plasma of renovascular hypertensive patients and control subjects using either homologous human or heterologous sheep renin substrate. The results suggest that, in addition to the renin concentration other factors are relevant to chronic high blood pressure in renovascular hypertension.
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PMID:Kidney and plasma renin in human renovascular hypertension. 100 43

Sar1-Ala8-angiotensin II was infused intravenously (10 mug/kg/min) in 14 patients with renovascular hypertension, including 11 with renal artery stenosis. Brachial artery pressure and heart rate remained unchanged in six patients who were on a daily sodium intake of 130 mEq. In 12 tests performed after sodium depletion, the decrease in mean arterial pressure ranged from 13 to 76 mm Hg and showed a significant correlation with the plasma renin concentration prevailing immediately before the infusion of the drug (r = 0.81; p less than 0.001). The hypotensive response was due to a drop in total peripheral resistance. Heart rate and cardiac output showed slight increases 10 min after the start of saralasin infusion.
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PMID:Haemodynamic effects of Sar1-Ala8-angiotensin II in patients with renovascular hypertension. 101 67

In 22 hypertensive patients with unilateral renal artery stenosis (RAS) and in 8 patients with unilateral or bilateral renal or renal arterial disease, plasma renin activity (PRA), renin substrate (PRS), and angiotensin II (AT II) concentrations were measured in both renal veins and in a peripheral vein 1-2 h after stimulation of renin secretion by injection of frusemide. In patients with elevated PRA in venous blood from a kidney with RAS, AT II was either also elevated, lower than or equal to PRA in peripheral blood, while the contralateral kidney almost invariably extracted AT II. In the 8 patients with variable renal diseases, the concordance between PRA and AT II measurements was better. Results suggest that AT II measurements in renal venous blood are less useful in assessing the functional significance of a RAS than those of PRA. Since PRS is not different in venous plasma of the diseased and the normal kidney, PRA measurements can be regarded as proportional to plasma renin concentration in this condition.
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PMID:Renin, renin substrate and angiotensin II concentration in renal venous blood. 102 64

Angiography is the most important diagnostic procedure for evaluation of renovascular hypertension. Technique and limits of this method as well as possible ways of improving its diagnostic value are discussed. The pathogenetic significance of a renal artery stenosis in hypertension and the prognosis for a vascular surgical intervention is discussed in the light of bilateral renin determination and the 138 Xe method of measuring intrarenal hemodynamics.
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PMID:Angiographic aspects of renovascular hypertension. 102 71

In hypertensive patients with unilateral renal artery stenosis, intravenous diazoide increased renal vein renin activity more on the involved side than on the contralateral side, whereas, in a group with predominantly unilateral renal parenchymal disease, the increase in renal vein was similar for both kidneys. In patients with bilateral renal artery stenosis, the use of diazoxide was helpful in lateralizing the dominant ischaemic lesion. Diazoide administration appears to be a safe, rapid and convenient method of increasing the sensitivity of the renal vein renin test used in predicting the outcome of surgical treatment of renovascular hypertension. Bilateral renal vein renin determination of established value in the diagnosis of functional renal ischaemia. 1-4 However, in the use of this procedure to predict the efficacy of corrective surgery, false positive and false negative results still occur. Thus, various manoeuvres which stimulate renin release have been employed to improve the sensitivity of the test. 5-7 We report a new application the practical approach to of this procedure in the diagnosis of renal hypertension, which both basal and stimulated levels of renal venous renin activitity can be measured during a brief period of bilateral renal vein catherization.
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PMID:Diazoxide-induced renin release in diagnosis of remediable renovascular hypertension. 106 96

1. A prospective study was undertaken in seventy-eight patients with renal hypertension (fifty-eight with renovascular disease and twenty with renal parenchymal disease), after their presentation to an advisory group as possible candidates for surgical management. 2. Vascular repair and/or nephrectomy were performed in forty-four patients, and the remainder were treated with anti-hypertensive drugs. The control of blood pressure was then assessed over periods of 6-70 months. 3. Of the patients treated surgically, fifteen (34%) were normotensive without medication and fifteen had improved blood pressure control; the morbidity rate was the same as in the medically treated group, but mortality was lower and blood pressure control was better, particularly among patients under 40 years of age. 4. Surgery undertaken primarily to conserve renal function was beneficial in four of nine patients with bilateral renal artery stenosis and severe, progressive uraemia. 5. The blood pressure response to surgical correction of unilateral renal lesions was predicted correctly by the preoperative renal vein renin ratio in fifteen of eighteen cases.
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PMID:Surgical intervention in severe and complicated renal hypertension: Report of the Sydney Renal Hypertension Group (1969-75). 107 15

Renal vein renin ratios were determined in hypertensive patients, 19 with renal artery stenosis, 7 with renal artery occlusion and 13 with unilateral renal hypoplasia. Twenty-one of these patients were treated surgically. Renal vein renin ratios of greater than or equal to 1.5 were associated with high frequency of operative success, but ratios less than 1.5 by no means excluded good surgical results.
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PMID:Renal vein renin ratio. Predictive value in renal and renovascular hypertension. 107 63

The effect of propranolol therapy on the mean arterial pressure (MAP) and plasma renin activity (PRA) was studied in three groups of hypertensive patients who were also treated with saliuretics. Group A: In 14 patients with essential hypertension on chlorthalidone treatment, an additional daily dose of 640 mg propranolol for two months led to a significant reduction of the MAP (from 124 to 105 mm Hg) and PRA (from 5.3 to 2.0 ng AI/ml/hr standing). There was no correlation between MAP reduction and either the original levels or change in PRA. Group B: In 14 patients with essential hypertension and 5 with renal artery stenosis studied on a fixed salt intake, the plasma and extracellular volumes, PRA, and blood pressures were recorded before and after three days of diuretic induced salt depletion and, with maintenance of the depleted state, after three days of propranolol. Salt depletion resulted in a decrease in MAP from 132 to 128 mm Hg (NS), and PRA increased from 3.4 to 22.3 ng AI/ml/hr (P less than 0.01). There was no correlation between change in MAP and PRA control values, PRA change, or any of the volume parameters. Addition of propranolol was followed by a rapid MAP decrease to 111 mm Hg (P less than 0.01), and the PRA dropped to a mean of 8.5 (P less than 0.01). No correlation was found between change in MAP and change in PRA. The patients with renal artery stenosis did not differ in their reactions from those with essential hypertension. Group C: In five patients with moderate renal failure and normal to expanded 82-Br distribution volume, propranolol lowered MAP by 10% and lowered the PRA in all five. Salt depletion by furosemide to 82-Br volumes below normal resulted in a 10% decrease of MAP and a marked rise in PRA. In this state propranolol was followed by a further MAP reduction of 18% and a decrease in PRA. There was no quantitative relationship between MAP and PRA change during either of the treatment regimes. It is concluded that in various forms of hypertension, the blood pressure can be effectively lowered by combining diuretics and propranolol regardless of the pretreatment PRA level.
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PMID:Effect of salt depletion and propranolol on blood pressure and plasma renin activity in various forms of hypertension. 109 56

The review discusses the pathophysiology of the renal mechanisms of blood-pressure control. The physiology of the renin-angiotensin system is described and the mineralo-corticoid function has also been considered. The implications of alterations of these systems in various nephropathies are briefly summarized (renal artery stenosis, infarction, Page's syndrome, acute glomerulonephritis, essential hypertension a.o.).
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PMID:[Pathophysiology of renal hypertension (author's transl)]. 110 Dec 91


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