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 authors studied plasma renin activity (PRA), urinary epinephrine, norepinephrine and dopamine excretion and their mutual relationships in 54 healthy subjects under basal (recumbent) conditions and age-related orthostatic changes in these parameters. The test subjects were divided into six 10-years groups, according to their year of birth (1901-1910 to 1951-1960). In the oldest groups (1901-1910 and 1911-1920), both basal PRA values and norephrine and epinephrine excretion and their postural increase were smaller than in younger subjects. Conversely, urinary dopamine excretion and the dopamine/norepinephrine and epinephrine ratio rose with advancing age. There were no significant differences between the plasma sodium and potassium concentrations in the various groups. Urinary aldosterone excretion was slightly higher in the oldest group than in the others, but was still within the control value limits. The intravenous administration of Inderal reduced both resting PRA values and the orthostatic increase in the youngest age groups, so that their PRA approached the values in older subjects. Higher norepinephrine and epinephrine excretion and the lower dopamine/norepinephrine and epinephrine in young subjects may play a role in their higher PRA, especially in the orthostatic reaction. Diminution of sympathetic activity, with lower norepinephrine and epinephrine excretion and relatively high dopamine excretion, may have a direct bearing on the lower PRA values in older subjects. The diminished capacity of older subjects for catecholamine mobilization and raised renin secretion during an orthostatis stress may be related to the higher incidence of orthostatic forms of hypotension in old age.
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PMID:Influence of age on orthostatic changes in plasma renin activity and urinary catecholamines in man. 12 10

The urinary excretion of free noradrenaline (NA), adrenaline (A), dopamine (DA), the DA/NA ratio in the urine, plasma renin activity (PRA) and their mutual relationship were investigated in 71 patients suffering from different types of arterial hypertension. In spite of the fact that the mean values of excreted catecholamines, with the exception of pheochromocytoma, lie within the range of values found in healthy controls, certain differences were found in spectrum of excreted catecholamines. In patients with labile, malignant and renovascular hypertension and in pheochromcytoma the higher mean excretion of NA and the low DA/NA ratio was accompanied by the higher PRA in comparison with fixed benign essential hypertension. On the other hand, in hypertension with low PRA (essential hypertension with suppressed renin and Conn's syndrome) a low excretion of NA and high DA/NA ratio was found. There was a significant, if not even very close negative correlation between the PRA and DA/NA ratios both in recumbent and upright position. The rise of PRA on standing up was followed by an increased excretion of NA while the excretion of DA did not change or decreased. Hence the DA/NA ratio when standing up showed a decreasing tendency as compared with values when lying down. Application of the beta-blocker Inderal decreased the PRA and the blood pressure not only in juvenile hypertensive patients with hyperkinetic circulation but also in the early phases of renovascular hypertension. It thus appears that endogenous catecholamines, first of all the ratio between the renin-inhibiting DA and the renin-stimulating NA, participate as one of several factors in the regulation of secretion and of the plasma levels of renin not only in juvenile hypertensive patients with hyperkinetic circulation but also in other types of hypertension.
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PMID:Relationship between plasma renin activity and urinary catecholamines in various types of hypertension. 97 8

The increase in aldosterone secretion that occurs in response to Angiotensin II (AII) is enhanced when normal humans are in external balance on a low salt diet. The responsible mechanism has not been identified. Angiotensin converting enzyme inhibition reduces blood levels of AII and aldosterone, but does not decrease PRA or AI and does not modify adrenal responsiveness to AII in the sodium-depleted state. This study was designed to assess the possibility that the enhanced adrenal response reflects plasma renin activity (PRA), plasma AI concentration, or catecholamines acting via a beta adrenergic receptor. Nine healthy males were studied when in balance on a high sodium intake (200 mmol Na/day), a low sodium diet (10 mmol Na) and after 4 days of beta adrenergic blockade with either nadolol or propranolol. The adequacy of beta adrenergic blockade was assessed with a postural stimulus and significant blockade was achieved, somewhat more with nadolol (40 mg/day) than with propranolol (Inderal LA, 80 mg every 12 hrs). Beta blockade enhanced the renal vascular and pressor response to AII but did not modify the adrenal response to posture or to AII. This study confirms the role for AII levels in the modulation of renal vascular and pressor responses to AII and rules out a role for PRA, AI, or catecholamines acting via a beta adrenergic receptor in the modulation of adrenal responsiveness to AII.
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PMID:Renal and adrenal responsiveness to angiotensin II: influence of beta adrenergic blockade. 151 63

Hemodynamic and humoral indices were studied in patients with juvenile hypertension before and after a months treatment course with obsidan. The beginning of the disease was in 18% distinguished by an increased thickness of the wall and interventricular septum. Obsidan treatment (0.5 mg/kg of body weight) resulted already during the first 2-4 weeks and then on the 3 and 6 month in an improvement of the general condition, normalization of the systolic pressure, cessation of tachycardia, reduction of the elevated cardiac index, reduction of the rate of circular shortening of the myocardial fibers, plasma renin activity and amount of blood aldosterone. Resistance to the effect of obsidan was noted in 10.5%. Some patients showed side-effects.
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PMID:[Effect of obzidan on hemodynamic indices and the renin and aldosterone levels of the blood plasma in patients with juvenile hypertension]. 267 68

The aim of the study was to prove the correlations between systolic and diastolic blood pressure (BP), heart rate (HR) and plasma renin activity (PRA) under mental arithmetic stress without and with beta-blockade. 22 male hypertensive patients (aged 19-39 years) were examined, divided into a group treated with d, 1-propranolol (Obsidan) and a control group receiving placebo. Under arithmetic stress the kinetics of systolic BP showed no differences even after beta-blockade. In contrast, the increases of HR and PRA before, during and after mental arithmetic were either significantly reduced (HR) or completely blocked (PRA) under beta-blockade. However, these suppressions of HR and PRA did not prevent the stress-induced elevations of systolic and diastolic BP under beta-blockade.
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PMID:[The blood pressure-regulating role of the renin-angiotensin system in essential hypertension before and after emotional stress]. 332 70

The response of the adrenocortical glomerular zones to different aldosterone-stimulating and aldosterone-inhibiting effects was analyzed in 178 patients with pronounced thyrotoxicosis. Basal indices of aldosteronemia in the patients under examination did not differ from those of the controls, whereas the plasma renin activity, hormone and its 3-hydroxy metabolite excretion with the urine significantly increased. Obsidan blocked renin secretion and lowered the blood plasma aldosterone content. Prednisolone, dexamethasone and hydrocortisone, inhibiting adrenocorticotropic function, hindered aldosterone secretion, whereas injections of a synthetic ACTH analog synacten and insulin, mobilizing the hypothalamic-hypophyseal-adrenocortical system, markedly enhanced the blood plasma aldosterone level. Therefore, the response to the drugs, activating and blocking aldosterone secretion in patients with thyrotoxicosis, was completely adequate and sometimes even more intensified. Further investigation of causes, inducing an increase in the activity of the renin-angiotensin system in thyrotoxicosis, is necessary. Studies of the factors, capable of influencing aldosterone secretion, are in progress.
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PMID:[Regulation of aldosterone secretion in patients with thyrotoxicosis. I. Role of the renin-angiotensin system and corticotropin in the development of secondary hyperaldosteronism in patients with thyrotoxicosis]. 630 81

The effect of obsidan, mercazolil and their combinations on the plasma and erythrocytic potassium and sodium content as well as on the plasma calcium and magnesium concentration was studied under clinical conditions in 107 patients with a visceropathic stage of toxic goitre. Obsidan was given orally in a dose of 1.5 to 2 mg/kg and mercazolil in a dose of 0.5 mg/kg daily within 10 successive days. Obsidan treatment led to an increase in plasma and erythrocytes of the potassium concentration and plasma magnesium content, while the level of sodium in plasma and erythrocytes as well as of plasma calcium reduced. Mercazolil treatment (control group) exerted no significant effect on the test characteristics. It is concluded that obsidan effect on the blood calcium and sodium concentration is mediated through its action on the renin-angiotensin-aldosterone system.
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PMID:[Effect of obsidan on blood electrolyte content in toxic goiter]. 689 54

In a randomized trial of pulsatile vs nonpulsatile cardiopulmonary bypass for coronary artery surgery, we studied hemodynamic and hormonal responses. Anesthesia did not produce a response but, from the time of the incision, cortisol and antidiuretic hormone levels and plasma renin activity all increased. Cortisol levels continued to rise after surgery, whereas the other began to fall. Systemic vascular resistance fell dramatically during cardiopulmonary bypass but rapidly rose after bypass with a reciprocal change in cardiac index. We did not see the changes ascribed to nonpulsatile bypass by others. There ws no difference between our pulsatile and nonpulsatile cases. High-flow cardiopulmonary bypass, vasodilating inhalation anesthesia and continuation of Inderal therapy may account for our results.
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PMID:Pulsatile cardiopulmonary bypass: failure to influence hemodynamics or hormones. 699 24

Obsidan (propranolol) monotherapy was investigated for the effect on the density of lymphocytic beta2-adrenoreceptors (B max), the activity of lymphocytic homogenates adenylate cyclase (AC), plasma renin activity (PRA), aldosterone concentration (A) and plasma catecholamines (CA). Obsidan treatment brought about a 40% increase in B max without a significant changes in AC activity. Contrary to a significant fall in PRA, A and norepinephrine in plasma reduced insignificantly. Changes in B max correlated with its baseline level (r = -0.56, p < 0.01), PRA (r = 0.57, p < 0.01) and A level in plasma (r = 0.62, p < 0.01). No significant correlations appeared between hypotensive effect of the drug and drug-related changes in B max and AC activity, while PRA and A concentrations showed such dependence. B max and before treatment mass of the left ventricular myocardium correlated significantly (r = = 0.595, p < 0.01). A small decrease in the myocardial mass followed obsidan administration, being related to B max (r = = 0.497, p < 0.05). It is concluded that obsidan-induced changes in lymphocytic beta 2-adrenoreceptors correlate with alterations in the activity of renin-angiotensin-aldosterone system and myocardial hypertrophy dynamics.
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PMID:[The effect of obzidan monotherapy on the beta 2-adrenoreceptors of the lymphocyte adenylate cyclase system in hypertension patients]. 791 13