Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033687 (proteinuria)
 24,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although the precise etiologic incitant of the minimal lesion idiopathic nephrotic syndrome of childhood is not known, it is likely that a host mechanism mediates the permeability alterations of the glomerular capillary wall resulting in massive proteinuria. As a first step in examining the possibility that local kinin release may account for the proteinuria in this disorder, two parameters of the plasma kinin-generating system, plasma prekallikrein and kallikrein inhibitor, were assayed during 27 nephrotic episodes in 21 corticosteroid-responsive children. Plasma kallikrein was assayed by means of its esterase activity on a synthetic arginine ester substrate, N-alpha-tosyl-L-arginine methyl ester (TAMe), after activation of Hageman factor by kaolin. This activity, after subtraction of spontaneous arginine esterase activity (i.e., TAMe esterase activity measured in plasma not exposed to kaolin) is derived from prekallikrein. Plasma prekallikrein activity in 11 normal children was 99.6 +/- 2.9 mumol TAMe hydrolyzed/ml plasma/hr (mean +/- SEM). Kallikrein inhibitor was quantified in arbitrary units. Kallifrein inhibitor activity in 11 normal children was 0.94 +/- 0.04 units. During the overt nephrotic syndrome, before initiation of intensive daily corticosteroid treatment, mean values were: prekallikrein, 58.5 +/- 7.24 mumol/ml/hr; and kallikrein inhibitor, 0.35 +/- 0.06 units. After corticosteroid-induced remission occurred, mean values were: plasma prekallikrein, 118.6 +/- 3.2 mumol/ml/hr; and kallikrein inhitor, 0.78 +/- 0.03 mumol/ml/hr. Both parameters were again assayed in 14 of the 21 children after complete cessation of corticosteroid treatment. Plasma prekallikrein was normal, 99.6 +/- 4.8 mumol/ml/hr; but kallikrein inhibitor was still somewhat depressed, 0.84 +/- 0.03 units. A subset of 9 patients had marked depression of plasma prekallikrein to levels less than 20 mumol/ml/hr and essentially undetectable inhibitor activity. Serum alpha-2 macroglobulin was elevated in nephrotic patients: mean value during relapse, 862 +/- 29 mg/100 ml; during corticosteroid-maintaining remission, 615 +/- 29 mg/100 ml. After cessation of corticosteroids, mean serum level was 481 +/- 20 mg/100 ml. The proportional reduction of plasma prekallikrein and kallikrein inhibitor suggested that an enzyme-inhibitor complex formed in vivo, perhaps at a local site of activation in proximity to the glomerular basement membrane. These data suggest that the plasma kinin-generating system may be the host effector mechanism subserving the increased glomerular capillary permeability in the minimal lesion nephrotic syndrome of childhood.
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PMID:A study of the plasma kinin-generating system in children with the minimal lesion, idiopathic nephrotic syndrome. 5 8

Main components of kinin system, the arginine-esterase activity and proteinase inhibitors were estimated in blood serum of patients with nephrotic syndrome of various etiology (glomerulonephritis, amyloidosis, systemic lupus erythematous) and also in patients with latent nephritis and in healthy donors. Content of all the kinin system components (kallikreinogen, kininogen and kininase 1) proved to be increased in all the forms of nephropathy studied. Free kallikrein was found in blood serum of patients with nephrotic syndrome as distinct from healthy persons and patients with latent nephritis. The arginine-esterase activity, which shows the level of trypsin-like proteinases, was altered dissimilarly, depending on the nephrotic syndrome etiology: it was maximally increased in nephrotic syndrome of amyloid genesis and decreased in patient with systemic lupus erythematosus. High content of kallikrein and kininase I with simultaneous decrease in kininogen was typical for patients with severe form of nephrotic syndrome. Impairment of kidney in nephrotic syndrome was also characterized by an increase in alpha1-antitrypsin and in the total antitryptic activity, which reached the maximal value in nephrotic syndrome of the I degree and decreased at the II degree of the disease. In nephrotic syndrome content of alpha2-macroglobulin was maximally increased at the II degree of nephrotic syndrome and decreased in severe form of the disease. The primary alteration in content of proteinase inhibitors and high level of kinin system components were assumed to determine the conditions for activation of kinin system in blood serum and to impair the nephrotic syndrome pathogenesis, which was complicated by systemic manifestations. High content of kinin system components was apparently determined by the increased synthesis in liver tissue in response to inflammation and massive proteinuria; kininase I and alpha2-macrolgobulin, as proteins with high molecular weight, were likely to be selectively retained in blood circulation when the capillary penetration was increased.
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PMID:[State of the kinin system and level of serum proteinase inhibitors in latent nephritis and the nephrotic syndrome of different etiology]. 7 Jan 11

Splenectomised calves in metabolism cages were infected with Babesia bovis. During the infection, urine samples were collected and analysed for electrolytes, proteins, kinin, and urinary kallikrein. During the later stages of the infection there were significant reductions in urinary volume, water intake, urinary kinin, kallikrein, and electrolytes. Proteinuria was detected from 3--8 days postinfection of which 15--20% was haemoglobin and most of the remainder was albumin (70--75%). Fibrin degradation products, fibrinogen-like products, and haptoglobin were not detected. Degeneration of cortical tubules was detected by histological studies. As these tubules produce urinary kallikrein it seems probable that diminished glomerular blood flow and hence glomerular filtration rate are due to decreased production of this enzyme.
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PMID:Acute Babesia bovis infections: renal involvement in the hypotensive syndrome. 49 8

Urinary kallikrein excretion was studied in two types of experimentally induced renal disease: anti-glomerular basement membrane nephritis (20 rats) and aminonucleoside nephrosis (five rats) with appropriate controls (23 rats) for a period of 6 to 9 weeks following disease induction. In both models there was a prompt significant decrease (p less than 0.01 - 0.001) in urinary kallikrein excretion associated with proteinuria but unrelated to urinary sodium and potassium excretion and urinary volumes. In antiglomerular basement membrane nephritis the fall in kallikrein excretion occurred within the first 24 hours concurrent with the onset of proteinuria. In aminonucleoside nephrosis the decrease antedated the onset of proteinuria by 48 hours beginning within the first 24 hours following injection of the aminonucleoside. Kallikrein inhibitors were not demonstrable in the urines of diseased animals from either model. The mechanism of the decrease in kallikrein excretion in immune and nonimmune glomerular disease associated with proteinuria is unknown.
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PMID:Urinary kallikrein in experimental renal disease. 93 67

Male weanling Wistar rats received 200 micrograms/ml of mercury (Hg), as HgCl2, in drinking water for 180 days. At the end of the treatment, systemic arterial blood pressure was augmented, cardiac inotropism was reduced, and heart rate was unchanged. Light and electron microscopical studies of the kidney showed a mesangial proliferative glomerulonephritis in about 80% of the glomeruli. Tubular cells showed reduction of the acid phosphatase activity, which was related to functional abnormalities of the lysosomes. In the 24 hour urine samples of the Hg exposed rats, there was slight reduction of kallikrein activity, but evident proteinuria was not present in all samples. Plasma renin activity was reduced, that of angiotensin I-converting enzyme was augmented, and plasma aldosterone concentrations were unchanged. Mercury was accumulated mostly in the kidney of the Hg treated animals; and the content of Hg in the heart was higher than in the brain. These data show that chronic exposure to Hg acts on the kidney with complex mechanisms of toxicity; these contribute to modify systemic haemodynamics.
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PMID:Renal mechanisms in the cardiovascular effects of chronic exposure to inorganic mercury in rats. 157 Dec 92

Albuminuria (UAlbV) can be reduced by converting-enzyme inhibitors (CEI), but the hormonal mechanism responsible for this effect has not previously been defined. Since CEI increase kinin activity as well as reduce angiotensin II (ANG II) activity, experiments were performed to determine the effect of isolated alterations in kinin and ANG II metabolism on UAlbV in rats with passive Heymann pephritis. Phosphoramidon was used to potentiate kinin activity without altering ANG II synthesis. Aprotinin was utilized in combination with the CEI, enalapril, to prevent the increase in kinin activity caused by CEI. UAlbV and the fractional renal clearance of albumin (FCAlb) decreased significantly after either phosphoramidon or enalapril, although only enalapril reduced blood pressure. Glomerular filtration rate (GFR) was not affected by either drug. Phosphoramidon did not affect plasma renin activity (PRA) or the pressor response to angiotensin I (ANG I), indicating that ANG II synthesis was not altered. Aprotinin prevented the reduction in UAlbV and FCAlb produced by CEI but not the hypotension, elevated PRA, or ANG I pressor blockade produced by CEI. Aprotinin alone had no effect on UAlbV, GFR, PRA, or blood pressure. UAlbV can be reduced by increasing kinin activity by a mechanism that is not dependent on suppression of ANG II activity or reduction in GFR or blood pressure. CEI may reduce proteinuria as a result of their action on the kallikrein-kinin system rather than on the renin-angiotensin system.
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PMID:Effects of modulation of renal kallikrein-kinin system in the nephrotic syndrome. 169 47

Twenty-four-hour urine kallikrein excretion (Uka), urine protein excretion, renal sodium handling, and the activity of the renin-angiotensin-aldosterone system were serially studied in 11 children at three different stages of the minimal change nephrotic syndrome (MCNS)-edema forming state, proteinuric steady state in which a relapse of the disease was just starting but no edema as yet and remission. The value for Uka was significantly increased in the edema forming state in contrast to the normal values of proteinuric steady state and remission. Serum sodium concentration was only decreased in the edema forming state and the degree of hypoalbuminemia and proteinuria did not differ between the edema forming and proteinuric steady states. Urine volume, absolute and fractional sodium excretion were significantly decreased in the edema forming and proteinuric steady states as compared with those in remission, suggesting that sodium retention was present in both states of the disease although the change in these parameters was more profound in the edema forming state than in the proteinuric steady state. Creatinine clearance did not differ among each stage of the disease. Plasma renin activity and plasma aldosterone concentration were significantly increased in the edema forming state as compared with those in the proteinuric steady state and remission. Plasma renin activity and plasma aldosterone concentration were significantly correlated directly with Uka and plasma aldosterone concentration was correlated inversely with urine sodium excretion. No relation was noted between Uka and other variables.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Urine kallikrein excretion in relation to renal sodium handling in minimal change nephrotic syndrome. 175 72

Involvement of the kallikrein-kinin system in the pathogenesis of renal edemas may be mediated by increase of vascular permeability, proteinuria, diuresis and natriuresis. Proceeding from these points, in 27 patients with morphologically proved chronic glomerulonephritis and the nephrotic syndrome, the serum kallikrein activity and its 24-hour urinary excretion level were measured. According to their edematous syndrome severity, all the patients were divided into 2 groups: 1) 19 patients with moderate edemas; 2) 8 patients with severe ones. During the follow-up period, there were no essential changes in patients' body weights, and no significant differences between the groups in clearances and excreted fractions of sodium, potassium, chlorine, osmotically active substances, and in serum albumin and cholesterol levels, 24-hour protein losses and blood pressure. As compared to the healthy (n-20) in all the patients a substantial and statistically significant increase in kallikrein activity was revealed in serum and urine. Kallikreinemia and kallikreinuria were significantly higher in Group 2 than those in Group 1. In the total group of examinees a significant direct relationship was established between the urinary kallikrein activity and summary sodium and potassium excretion as well as between the serum kallikrein activity and chlorine clearance. A direct correlation between the serum kallikrein activity and proteinuria was also found. Thus, a role of the kallikrein-kinin system in development of glomerulonephritic edemas concurrent with the nephrotic syndrome is hetero-directional.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[The participation of the kallikrein-kinin system in edema formation in glomerulonephritis]. 185 8

The kallikrein-kinin system of the blood serum (prekallikrein and kallikrein) was studied in 68 patients with chronic glomerulonephritis with the purpose of determining the significance of this system in the origin of proteinuria, protein content in the morning portion of urine and 24-hour portion. Linear correlation analysis revealed a direct relation of the levels of kallikrein and prekallikrein in the blood serum the morning and 24 losses of protein in patients suffering of glomerulonephritis with an isolated urinary syndrome (18 patients), nephrotic (27 patients) and glomerulonephritis with arterial hypertension.
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PMID:[THe role of the kallikrein-kinin system in the origin of proteinuria in glomerulonephritis]. 208 9

The present study was designed to determine urinary excretion of kallikrein(KAL)-kinin as well as prostaglandin (PG) E2, TXB2 and 2,3-dinor-TXB2, a major urinary metabolite of TXA2 synthesized in platelets, by specific RIAs in patients with diabetes mellitus (DM). KAL or kinin excretion in 26 type II DM did not differ from control values obtained in 18 age-matched healthy subjects (C), although DM with HbA1 greater than 11% excreted less KAL. Urinary PGE2 excretion (7.6 +/- 2.8 ng/mg creatinine, mean +/- SE) was significantly lower in DM compared to C (17.5 +/- 3.9, p less than 0.05), while DM excreted more TXB2 (0.57 +/- 0.09, p less than 0.01) and 2,3-dinor-TXB2 (0.56 +/- 0.12, N.S.) than C (0.19 +/- 0.02 or 0.33 +/- 0.01). DM with or without mild proteinuria demonstrated lower PGE2, but higher TXB2 and 2,3-dinor-TXB2 excretion. A positive correlation of TXB2/2,3-dinor-TXB2 with proteinuria was observed in this group. However, in DM with massive proteinuria over 500 micrograms/mg creatinine, TXB2 and 2,3-dinor-TXB2 excretion decreased to levels almost identical to C. As a whole, a ratio of TXB2 to PGE2 or 2,3-dinor-TXB2 in DM was significantly higher than in C. The results suggest that a relative preponderance of TXB2 to 2,3-dinor-TXB2 may indicate an augmented renal, in addition to platelet, TXA2 synthesis. An excessive vasoconstrictive and proaggregatory TXA2 renal synthesis, concomitant with a decrease in vasodilatory and antiaggregatory PGE2, may have profound effects on renal functions such as protein excretion in DM.
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PMID:Increased renal TXA2 synthesis in diabetes mellitus: simultaneous determination of urinary TXB2 and 2,3-dinor-TXB2. 233 36


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