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 cytokine interleukin-1 (IL-1) has a variety of effects in the kidney involving induction of nephritis and renal injury. In addition, recent reports suggest that IL-1 regulates natriuresis and renin secretion in the kidney. To examine the potential sites of action of IL-1 in the kidney, we used iodine-125-labeled recombinant human interleukin-1 alpha ([125I]IL-1 alpha) to identify and characterize IL-1 receptors in crude membrane preparations of mouse (C57BL/6) kidney. The binding of [125I] IL-1 alpha was linear over a broad range of membrane protein concentrations, saturable, reversible, and of high affinity, with an equilibrium dissociation constant (Kd) of 66 +/- 10 pM and a maximum number of binding sites of 1.04 +/- 0.24 fmol/mg protein. In competition studies, recombinant human IL-1 alpha, recombinant human IL-1 beta, and a weak IL-1 beta analog (IL-1 beta+) inhibited [125I]IL-1 alpha binding to mouse kidney in parallel with their relative bioactivities in the T-cell comitogenesis assay, with inhibitory binding affinity constant (Ki) values of 28 +/- 19, 53 +/- 23, and 5560 +/- 2098 pM, respectively; rat/human CRF and human tumor necrosis factor had no effect on [125I]IL-1 alpha binding. In autoradiographic studies, IL-1 receptors were heterogeneously distributed in the kidney, with significantly higher densities present in the medulla than in the cortex. To study the effects of endogenous IL-1 in modulating [125I]IL-1 alpha-binding sites in kidney, we injected 30 micrograms of the bacterial endotoxin lipopolysaccharide (LPS) to mice ip. Autoradiographic studies demonstrated substantial decreases in [125I]IL-1 alpha binding in both the kidney cortex (control, 34.7 +/- 6.2 fmol/mg tissue equivalent; LPS, 11.3 +/- 0.3; P less than 0.05) and medulla (52.7 +/- 8.1 vs. 26.0 +/- 1.0; P less than 0.05) 24 h after injection of LPS. Saturation studies in whole kidney homogenates demonstrated that the LPS-induced decrease in [125I]IL-1 alpha binding was primarily due to a down-regulation of IL-1 receptors (i.e. decrease in the maximum number of binding sites). The identification of IL-1 receptors in kidney with characteristics similar to those of IL-1 receptors in the brain-endocrine-immune axis provides further support for a physiological role for IL-1 in regulating renal function.
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PMID:Interleukin-1 receptors in mouse kidney: identification, localization, and modulation by lipopolysaccharide treatment. 182 79

Water immersion (WI)-induced alterations of circulating plasma volume (PV), plasma renin activity (PRA), plasma levels of aldosterone (Ald), vasopressin (AVP) and atrial natriuretic peptide (ANP) were examined in 12 patients with noninflammatory acute renal failure (ARF) at the anuric/oliguric phase, in 20 hemodialyzed patients with chronic renal failure and in 15 healthy subjects. Patients with acute and chronic renal failure showed significantly elevated basal ANP concentrations (138.67 +/- 12.88 and 295.8 +/- 21.87 pg/ml, respectively) as compared with normals (74.54 +/- 4.1 pg/ml) and significantly elevated PRA (20.85 +/- 3.24 and 6.60 +/- 0.94 ng/ml/h, respectively versus 2.33 +/- 0.31 ng/ml/h), plasma levels of Ald (16.11 +/- 1.26 and 18.11 +/- 1.58 ng/dl, respectively versus 12.71 +/- 1.03 ng/dl) and AVP (6.95 +/- 0.62 and 6.08 +/- 0.54 pg/ml, respectively versus 2.68 +/- 0.48 pg/ml). After 2 hrs of WI a significant decline of PRA, Ald and AVP but an increase of ANP was noted in all examined groups. The absolute WI-induced increase in plasma ANP was significantly less marked in uremic patients than in normals. The endocrine profile of patients with ARF differed only quantitatively from that of patients with CRF both under basal and WI conditions. WI was followed by a significant increase of PV which was significantly more marked in patients with ARF (+ 16.42 +/- 1.73%) than in CRF (10.57 +/- 0.37%) and in normals (+11.3 +/- 1.6%). Only in healthy subjects a significant correlation was found between WI-induced changes of PV and ANP, PRA and Ald, and between PRA and AVP.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Water immersion-induced alterations of plasma atrial natriuretic peptide level and its relationship to the renin-angiotensin-aldosterone system and vasopressin secretion in acute and chronic renal failure. 252 41

Corticosteroid-dependent hypertension can be cured by surgical removal of steroid-producing adrenocortical adenomas or, in case of other etiopathologic factors, specific drug therapy may be introduced for preventing irreversible complications of the hypertension process. In most cases, corticosteroid-dependent hypertension fails to manifest itself with clearcut endocrine symptoms. Therefore, an endocrine evaluation is strongly recommended in all patients with hypertension who are susceptible to hypokalaemia and whose blood pressure is poorly controlled with conventional antihypertensive drugs. The increased blood pressure in corticosteroid-producing adrenocortical adenomas may be attributed not only to the main glucocorticoid, cortisol, and the main mineralocorticoid, aldosterone, but also to the actions of weak mineralocorticoids which may be occasionally predominant. Adrenocortical adenomas including incidentalomas produce in different quantities at least 6 corticosteroids which play direct or indirect roles in hypertension. These adenomas are lacking autonomous hormone secretion and they respond to different regulatory impacts (i.e. stress and, by analogy, CRF or ACTH administration) with markedly-increased hormone secretion. Consequently, hypertension and hypokalaemia develop, often in the absence of other endocrine symptoms. The weak mineralocorticoids may not entirely account for the hypertension, although they may be useful indicators or may serve as precursors for the generation of more potent hypertensinogen steroids and steroid metabolites. This is patently indicated by the disappearance of hypertension, hypokalemia and mineralocorticoid-excess induced suppression of the renin-angiotensin system after the surgical removal of adrenocortical adenomas which produce only weakly-hypertensinogen corticosteroids.
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PMID:[The hypertensive role of corticosteroids in the light of adenoma of the adrenal cortex]. 266 40

The effects of ovine corticotropin releasing factor (o-CRF) on plasma aldosterone, 18-OH-corticosterone (18-OHB), plasma adrenocorticotropin (ACTH) and cortisol were determined in eight patients with primary aldosteronism, six with aldosterone-producing adenoma (APA) and two with idiopathic hyperaldosteronism (IHA). The results were compared with those in six normal subjects and eleven patients with essential hypertension (EHT, 5 with low renin and 6 with normal renin). In patients with APA, the peak plasma aldosterone and 18-OHB responses to 100 micrograms iv of o-CRF (226% and 113% increase from baseline, respectively) were greater than those in EHT and normal subjects. The net integrated aldosterone and 18-OHB responses (840 +/- 156, and 419 +/- 121 ng/dl.hr, respectively) were also significantly greater (p less than 0.01) in APA than those in normals and EHT. In two patients with IHA, both the peak and net integrated aldosterone response were smaller than those in APA, in spite of nearly identical plasma ACTH and cortisol responses. These results suggest that augmented responses of mineralocorticoids to o-CRF may be characteristic of aldosteronism due to APA, mediated by CRF-induced ACTH, and possibly other proopiomelanocortin (POMC)-derived peptides.
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PMID:Effects of corticotropin-releasing factor (CRF) on aldosterone and 18-hydroxycorticosterone in essential hypertension and primary aldosteronism. 283 82

Ovine corticotrophin-releasing factor (oCRF) (1 microgram/kg) and arginine vasopressin (AVP) (1 microgram/kg) were injected iv in sheep, both separately and in combination. Plasma levels of immunoreactive ACTH (IR-ACTH), cortisol, and aldosterone were measured for 3 h after the injections. Mean levels before injections were 8 +/- 4 pmol/l for ACTH, 7 +/- 3 nmol/l for cortisol, and 28 +/- 9 pmol/l for aldosterone. CRF caused a rapid rise in IR-ACTH and a peak level of 125 +/- 52 pmol/l was obtained 15 min after injection. Highest values for cortisol and aldosterone levels were 40 +/- 9 nmol/l and 64 +/- 13 pmol/l, respectively, 30 min after injection. AVP also increased IR-ACTH (maximum level: 202 +/- 77 pmol/l at 5 min) and aldosterone (128 +/- 36 pmol/l at 15 min), whereas the cortisol increase was lower than after CRF. Simultaneous injection of CRF and AVP produced an addition of the IR-ACTH response (295 +/- 82 pmol/l at 15 min), but the changes in cortisol levels were similar to those obtained after CRF alone and those in aldosterone levels resembled those induced by AVP alone. Plasma Na and K, osmolality, and plasma renin activity (PRA) were not modified by either CRF or AVP. It is suggested that the increase in aldosterone levels after CRF could be mediated by ACTH and that after AVP by an IR-ACTH peptide with less effect on cortisol secretion.
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PMID:Plasma adrenocorticotrophin, cortisol and aldosterone responses to ovine corticotrophin-releasing factor and vasopressin in sheep. 300 95

The acute effect on the renin-angiotensin system and the pharmacokinetic properties of delapril, a new angiotensin converting enzyme inhibitor and its active diacid metabolites (delapril diacid and 5-hydroxy delapril diacid) arising from delapril in vivo were investigated in 4 hypertensive patients with chronic renal failure (CRF: 4 males, average age 49.5 (37-64) years, mean Ccr 22.2 ml/min/1.73 m2) and 9 patients with essential hypertension (EH: 6 males, 3 females, average age 42.8 (28-61) years, mean Ccr 79.3 ml/min/1.73 m2). In CRF, following a single dose of delapril hydrochloride (30 mg), the biological half lives (t1/2) of delapril diacid and 5-OH-delapril diacid were 4.69, 12.88 hours, the maximum serum concentration (Cmax) and the area under the plasma concentration-time curve ([AUC]24(0)) of delapril and its diacid metabolites were 414, 797 and 435 ng/ml, and 658, 6400 and 5068 ng X h/ml, respectively. In EH, the t1/2 of delapril diacid and 5-OH-delapril diacid were 1.21, 1.40 hours and the Cmax and [AUC]24(0) of delapril and its diacid metabolites were 489, 635 and 229 ng/ml, and 572, 1859 and 948 ng X h/ml, respectively. The [AUC]24(0) in CRF were significantly increased as compared with those in EH. The cumulative urinary excretions were significantly lower in CRF than in EH. The serum angiotensin converting enzyme (ACE) was markedly inhibited in both groups up to 24 hours. The plasma concentration of angiotensin II decreased in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pharmacokinetics and acute effect on the renin-angiotensin system of delapril in patients with chronic renal failure. 303 May 95

Effects of captopril on arterial pressure (AP) and renal function were investigated in patients with non-malignant "benign" or malignant phase essential hypertension (EH group), or with chronic renal failure (CRF group). After captopril administration, AP and renal vascular resistance (RVR) decreased significantly, and renal blood flow (RBF) and plasma renin activity (PRA) increased in both groups. Glomerular filtration rate (GFR) increased in the EH group, but was unchanged in CRF. Filtration fraction decreased in the malignant hypertension and CRF groups. Significant correlations were found between baseline PRA and baseline RVR, and the captopril-induced decrease in mean AP, decrease in RVR, increase in RBF, and increase in GFR in the EH group, while these associations were not observed in CRF. These results indicate that the high AP, RVR, suppressed RBF and GFR in the EH group were closely related to activity of the renin-angiotensin system, but not so the low RBF and GFR in CRF. Small doses of captopril may improve impaired renal function in EH, and may not cause deterioration in the CRF group.
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PMID:Renal haemodynamics and comparative effects of captopril in patients with benign- or malignant-essential hypertension, or with chronic renal failure. 330 Oct 82

The syndrome of hyporeninemic hypoaldosteronism (SHH) is not infrequent in adults with chronic renal failure caused by chronic tubulointerstitial nephritis, but it has been reported rarely in children. We present a systematic study of the interrelation between renal excretion of potassium and the renin-aldosterone axis in 23 children with CRF of different and unselected causes. Twenty children with chronic renal failure never had hyperkalemia, and both renin and aldosterone were normally stimulated by intravenous administration of furosemide, whereas three patients had moderate hyperkalemia (serum potassium concentration between 5.3 and 5.6 mEq/L) and failed to raise plasma renin activity and aldosterone values in response to furosemide. There three patients with SHH had lower basal and stimulated values of fractional potassium excretion than did patients with normokalemic chronic renal failure. Fractional potassium excretion was curvilinearly related to glomerular filtration rate (GFR), but in all three patients with SHH it was lower than expected for the level of GFR present. Fractional sodium excretion was also related to GFR, but no abnormalities were found. Two patients had hyperchloremic metabolic acidosis. After furosemide administration, they excreted an acid urine with low ammonium content, features characteristic of type 4 or hyperkalemic renal tubular acidosis. Prostaglandin E2 excretion was also significantly related to GFR, and appeared appropriate in two patients with SHH. The identification of three patients with SHH among 23 with chronic renal failure of unselected causes suggests that this entity is not rare in childhood.
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PMID:Hyporeninemic hypoaldosteronism in children with chronic renal failure. 352 45

The authors studied the blood aldosterone, cortisol, and kalium levels, the plasma renin activity and the aldosterone urinary excretion following L-Dopa (0,50 g per os) administration in five patients affected by hypertension and six healthy control subjects, before and after the CRF-ACTH system suppression. The observed pattern shows that the aldosterone biosynthesis is inhibited also after the CRF-ACTH system has been suppressed. Therefore the authors conclude that the inhibiting action of L-Dopa on the aldosterone biosynthesis is mediated by the dopaminergic system stimulation.
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PMID:[The dopaminergic system and aldosterone secretion. II. Effect of L-dopa and dexamethasone on aldosterone biosynthesis]. 701 72

The behavioral and/or neuroendocrine reactivity to psychological (open-field exposure) and physiological (CRF challenge) stimulations, as well as adrenal tyrosine hydroxylase (TH) and phenylethanolamine N-methyl transferase (PNMT) activities were measured, at different ages, in the Roman high avoidance (RHA) and Roman low avoidance (RLA) rat lines that have been genetically selected on the basis of their divergent active avoidance behavior. The highest locomotor activity in the open field, associated to blunted prolactin and renin reactivity to an emotional stress and lower specific TH and PNMT activities, characterized the RHA rats of all ages. HPA axis reactivity to psychological and/or physiological stimulations was identical in young animals (14 weeks old) of the two lines. Nevertheless, it displayed with age maturation processes, since the amplitude of postopen-field secretion peak for ACTH was larger in RLA rats from 20 weeks on, the response to CRF being not increased until 42 weeks. These maturation processes could result from genetically influenced changes related to environmental stimulations. Therefore, the Roman lines may be an excellent model to study the interactions between the genetic and developmental factors controlling the coupling between both behavioral and neuroendocrine functions.
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PMID:Maturation of the behavioral and neuroendocrine differences between the Roman rat lines. 798 61


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