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)

It has been proposed that the aetiology, pathophysiological status, and effective treatment of hypertensives depends on concomitant plasma renin levels. Epidemiological data are scarce on the interrelations of plasma renin activity (PRA), BP and correlates of BP in the general population. Therefore, profiles of BP correlates were compared between low PRA groups and high PRA groups in a relatively healthy population of 321 Chinese government employees working in the Taipei area, in the summer of 1987. The characteristics of the two PRA groups were similar in body mass index, urinary sodium, chloride, calcium excretion and fasting parathyroid hormone. However, the high PRA group was younger, smoked more, and had a higher mean urinary potassium excretion. Fasting plasma glucose, uric acid, and creatinine levels were lower in the low PRA group. Positive relationships between BP and urinary sodium, chloride, potassium, calcium, plasma cholesterol, triglyceride, and glucose, independent of age and body mass index, were demonstrated in the low PRA group, where a volume expansion state may exist. However, in the high PRA state, uric acid, haemoglobin concentration, insulin and parathyroid hormone level were correlated more closely with BP than in the low PRA state. Further studies are needed to examine whether the differing associations between BP and risk factors in the high and low PRA groups reflect different compensatory mechanisms or aetiological factors.
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PMID:Correlates of blood pressure differ in high and in low plasma renin groups. 162 89

This study is aimed at examining the role of non-hemodynamic factors on the impaired microcirculation in patients with moderate essential hypertension. In a series of 31 patients (mean age, 47.8 +/- 1.1 years) with newly diagnosed untreated moderate essential hypertension (mean systolic blood pressure 161.7 +/- 2.0 mm Hg, mean diastolic blood pressure 102.4 +/- 1.5 mm Hg), parameters of the capillaroscopic examination of the finger microcirculation (mean number of capillaries, NRCAP), length of the capillaries (LECAP, microns), diameter micron) of the efferent (EFDI) and afferent (AFDI) apillaries, and mean red blood cell velocity (RBCV, microns/sec), which was measured by the flying spot technique, were correlated with a number of hormones (sampled after an overnight fast) including: plasma renin activity, aldosterone, and parathyroid hormone (PTH). A significant correlation (P less than .05) could be obtained between several parameters of the microcirculation and PTH:PTH (23.8 +/- 1.4 pg/mL)-NRCAP (14.9 +/- 0.5): r = -0.440, P = .013; PTH-AFDI (4.0 +/- 0.5 microns): r = 0.442, P = .012; PTH-EFDI (2.8 +/- 0.5 microns): r = 0.416, P = .019; PTH-RBCV (711 +/- 69 microns/sec): r = -0.351, P = .05. Furthermore, 24-h urinary norepinephrine (U-NOR) and afferent and efferent diameter of the capillaries intercorrelated significantly: U-NOR (46.0 +/- 6.2 micrograms/24 h)-AFDI: r = 0.439, P = .034; U-NOR-EFDI; r = 0.462, P = .025. This study shows that in patients with moderate essential arterial hypertension nonhemodynamic factors have an influence at the level of the microcirculation.
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PMID:Influence of nonhemodynamic factors on the microcirculation in moderate arterial essential hypertension. 178 51

Plasma levels of atrial natriuretic peptide (ANP), renin activity (PRA), and endothelin (ET) are often elevated in uremic patients on hemodialysis treatment. The profile of these vasoactive hormones and their relationships with hemodynamic indices in patients on continuous ambulatory peritoneal dialysis (CAPD), however, are not clear. We therefore measured plasma concentrations of ANP, PRA, ET, together with parathyroid hormone (PTH) in 17 patients (mean age 38.5 years) on maintenance CAPD over a period of 12 weeks. Baseline ANP, PRA, and ET levels were significantly higher than those of healthy subjects, and no significant changes in these indices were observed over the 12 week period. There was a significant positive correlation between levels of plasma ANP and PRA [rank correlation coefficient, R(s) = 0.496, p less than 0.05] as has been reported in cardiac failure. Despite the absence of clinically overt heart failure, a significant proportion (approximately 50%) of our patients demonstrated evidence of myocardial dysfunction on echocardiography. Furthermore, a significant positive correlation was demonstrated between plasma ANP and left atrial size [R(s) = 0.61, p less than 0.01] and an inverse correlation existed between plasma ANP and the left ventricular ejection fraction [R(s) = 0.51, p less than 0.05]. Twelve patients (71%) had biochemical evidence of hyperparathyroidism with raised levels of serum PTH. Our study demonstrates increased levels of plasma ANP, PRA, and ET in uremic patients on long-term CAPD. A positive correlation exists between plasma ANP and PRA suggesting their myocardial function may be compromised and this was confirmed on echocardiography. The possibility that high circulating PTH concentrations contribute to impaired cardiac function in such patients, deserves further study.
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PMID:Vasoactive hormones in uremic patients on continuous ambulatory peritoneal dialysis. 183 Feb 51

In a group of 36 untreated patients with mild to moderate essential hypertension (office systolic and diastolic blood pressures (BPs) 160 +/- 3.4 and 102 +/- 1.5 mm Hg, respectively), a 24-hour ambulatory BP monitoring and determination of left ventricular (LV) mass index according to the formula of Devereux were performed. After an overnight fast, blood samples were taken for the determination of serum aldosterone, plasma renin activity and serum parathyroid hormone. Urinary catecholamines were sampled for 24 hours. LV mass index (143.7 +/- 8 g/m2) did not correlate significantly either with office systolic or diastolic BP. The correlation of LV mass index with mean 24-hour systolic BP (145 +/- 3 mm Hg) was statistically significant: r = 0.395, p = 0.026. However, the best correlation was obtained with mean 24-hour diastolic BP (90 +/- 3 mm Hg) with r = 0.500 (p = 0.004). Urinary catecholamines were not correlated with LV mass index. LV mass index correlated significantly with plasma renin activity (r = 0.346, p = 0.050), and aldosterone (r = 0.559, p = 0.001). There was a very significant correlation between LV mass index and parathyroid hormone (r = 0.719, p = 0.00001) even after adjustment for mean 24-hour systolic and diastolic BPs. These results clearly demonstrate that ambulatory BP determinants but not office BP parameters are well correlated with LV hypertrophy in essential hypertension. Nonhemodynamic factors are important determinants of LV mass as well. Besides the renin-angiotensin-aldosterone system, parathyroid hormone appears to play an important role in cardiac hypertrophy.
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PMID:Influence of the arterial blood pressure and nonhemodynamic factors on left ventricular hypertrophy in moderate essential hypertension. 183 70

1. Renal handling of electrolytes, including calcium (Ca), in response to physiological saline infusion (20 mL/kg, i.v., for 2 h) as well as basal circulating levels of Ca-regulating hormones were compared in 27 hypertensive elderly females (mean age 80 +/- 9 years), in 44 normotensive elderly females (79 +/- 9 years) and in 19 young normotensive females (23 +/- 4 years). 2. The hypertensive elderly females showed excessive increase in urine volume and urinary excretions of sodium (Na), Ca and inorganic phosphate (P) in response to saline infusion, associated with slight but significant decrease in circulating levels of Na and ionized Ca compared with those in the other groups. These hypertensive elderly patients also showed characteristic features both in circulating blood pressure and Ca regulating factors; they showed significantly low levels of plasma renin activity and aldosterone concentration, significantly high plasma levels of atrial natriuretic peptide and noradrenalin, compared with those in young controls and normotensive elderly females. 3. Moreover they showed significant increase in basal serum levels of parathyroid hormone and 1,25-dihydroxyvitamin D, and significant decrease in basal serum levels of calcitonin, 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D, compared with those in the other groups. 4. These results suggest that the exaggerated natriuresis associated with excessive loss of Ca and P in urine may participate in the abnormality of Ca metabolism in low-renin hypertensive elderly patients.
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PMID:Calcium metabolism in elderly hypertensive patients: possible participation of exaggerated sodium, calcium and phosphate excretion. 183 82

The extracellular and intracellular concentrations of electrolyte were maintained by various systems including kidney and endocrine system. Although concentrations of electrolyte in the extracellular fluid were maintained in normal ranges in healthy elderly subjects, the reserve ability for the maintenance of electrolyte balance decreases with physiological aging. Occurrence of abnormality in electrolyte concentrations in extracellular fluid is thought to be related to pathological aging. The frequency of subjects with abnormal circulating concentrations of electrolytes, as well as abnormal rates of severe such abnormalities increase with age. Clinical characterization and differentiation of physiological and pathological aging are not always easy. On the other hand, the kidney is the central organ for maintenance of electrolyte homeostasis. Decrease in renal ability to retain electrolytes sometimes affect the features of disorders such as hypertension and osteoporosis of elderly subjects. Intravenous infusion of physiological saline at a dose of 20 ml/kg over 2 hr evoked excessive excretion of sodium, calcium and inorganic phosphate in the urine in hypertensive elderly patients and in some patients with senile osteoporosis. These subjects showed decreased levels of plasma renin activity and increased serum levels of parathyroid hormone and 1,25-dihydroxyvitamin D. These features indicate that abnormal renal metabolization of electrolytes involving abnormality of endocrine system may be a cause of, and modulate the clinical features of, some disorders of elderly subjects.
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PMID:[Physiological and pathological aging and electrolyte metabolism]. 189 25

Eleven hemodialyzed patients with uremia were examined for the effect of erythropoietin (EP) treatment carried out for 3 months on functions of different endocrine organs. EP treatment resulted in a decrease of the initial plasma levels of somatotropin, prolactin, follicle-stimulating and luteinizing hormones. EP treatment being over, there was a decrease in the plasma content of ACTH, cortisol and aldosterone. The treatment with EP was also associated with an insignificant rise of the plasma levels of parathyroid hormone and testosterone. EP treatment did not influence the plasma concentration of calcitonin and 25-OH-D. EP was found to exert no significant effect on the pituitary-thyroid reverse relationship. The 3-month treatment with EP eventuated in plasma renin activity inhibition as well as in an increase of the atrial level of natriuretic peptide in the plasma. EP treatment stimulated insulin secretion and reduced glucagon secretion. Finally, EP decreased the gastrin level and to a less degree the plasma level of pancreatic polypeptide.
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PMID:[The effect of erythropoietin treatment on endocrine organ function in patients with terminal-stage kidney failure on hemodialysis]. 194 56

Renal handling of Na and Ca in response to physiological saline infusion (20 ml/kg i.v. for 2 h) was compared between 27 hypertensive (mean +/- SD age 79.8 +/- 9.2 years) and 44 normotensive (79.1 +/- 4.1 years) senile females. Compared to the normotensive group, the hypertensive group showed statistically significant decreases in the basal values of serum Ca and PRA, and significant increases in basal circulating levels of parathyroid hormone and 1,25(OH)2D and in urinary excretions of Na, Ca and Pi in the 2-hour urine specimens during the saline infusion. These results suggest that the excessive excretions of Ca and Pi associated with exaggerated natriuresis may participate in aberration of Ca metabolism in low-renin hypertensive seniles.
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PMID:Exaggerated natri-calci-uresis and increased circulating levels of parathyroid hormone and 1,25-dihydroxyvitamin D in patients with senile hypertension. 195 61

There is a growing list of cells that are capable of detecting and responding to changes in the concentration of extracellular calcium. The two classic examples of this behaviour are the calcitonin-secreting parafollicular cells of the thyroid and parathyroid hormone-secreting chief cells of the parathyroid gland. A more recent addition to this list is the renin-secreting juxtaglomerular cell of the kidney. Particularly intriguing has been independently the discovery by two laboratories, that the resorptive cell of bone, the osteoclast, is capable of detecting changes in ambient calcium. A common theme amongst all these so called "calcium-responsive" cells is that extracellular calcium increases elevate intracellular calcium levels, and this intracellular signal is either stimulatory or inhibitory to the functional response. But how these cells detect changes in the concentration of extracellular calcium, and how these recognition events are subsequently transformed into intracellular signals that regulate cell function are somewhat less clear. The commentary reveals some recent developments that seemingly provide insights into these mechanisms, with special reference to the osteoclast.
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PMID:"Calcium receptors" on eukaryotic cells with special reference to the osteoclast. 196 12

Considerable interest has developed regarding the role of calcium in the regulation of blood pressure. Epidemiologic investigations, laboratory evaluations, and clinical trials all confirm that the relationship between calcium and blood pressure extends to include the pregnant state. On the basis of current information it is clear that calcium supplementation during pregnancy lowers blood pressure. Additionally, the effect of calcium on blood pressure may influence the incidence and/or gestational age of development of preeclampsia. Additionally, the effect on smooth-muscle relaxation detected in calcium-supplemented patients may affect the incidence of prematurity. Although the mechanism for these effects has not been entirely elucidated, calcium supplementation appears to affect circulating concentrations of parathyroid hormone and renin, which may modulate intracellular ionized calcium, resulting in the observed effect on smooth-muscle relaxation. This effect may also be responsible for reduced uterine activity and for a lowering of the incidence of prematurity.
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PMID:Pregnancy-induced hypertension and low birth weight: the role of calcium. 205 68


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