Urinary Enzyme Excretion Research Articles

Evaluation of enzymuria as an indicator of amikacin-induced renal damage in guinea pigs

Guinea pigs were injected subcutaneously for 10 days with amikacin (AK) at a dose of 0, 100,200 or 400 mg/kg body wt. per day. The total daily dose was administered in either a single injection or divided equally and given as two daily injections. After the 10 days of AK treatment, uptake of the organic cation, tetraethylammonium (TEA) into renal cortical slices was inhibited in a dose-related manner. Changes in renal tubular morphology also increased with higher doses. The urinary excretion of the enzymes, N- acetyl-β- d- glucosaminidase (NAG), and alkaline phosphatase (ALP) significantly increased during the course of AK treatment, however, due to the large intragroup variability, the daily fluctuations and the absence of any distinct trends in urinary enzyme excretion it was difficult to establish a dose-relationship between AK-induced renal damage and the resultant enzymuria. At doses of 100 and 200 mg/kg body wt., the two-injection regimen resulted in the greater renal accumulation of AK and damage as reflected by a greater inhibition of TEA uptake and greater changes in renal tubular morphology. In contrast, this difference in toxicity could not be detected with enzymuria again due to the large intragroup variability and the absence of discernable excretion patterns of NAG and ALP. Thus, neither NAG nor ALP appear to be suitable quantitative markers of AK-induced nephrotoxicity.

Cephaloridine Nephrotoxicity is Potentiated by Selenium Deficiency but not Copper Deficiency in Rats

Lipid peroxidation may contribute to the nephrotoxicity of cephaloridine, a beta-lactam antibiotic. Copper and Se may protect against free radical damage, and dietary Se deficiency potentiates cephaloridine nephrotoxicity. The objectives of this study were to further investigate potentiation of cephaloridine toxicity by Se deficiency and to determine whether Cu deficiency increases cephaloridine-induced injury. Weanling male Sprague-Dawley rats were fed adequate, Cu-deficient, Se-deficient, and Se and Cu-deficient diets for 4 wk and subsequently injected i.p. with cephaloridine (1200 mg/kg body wt) or saline. Nephrotoxic response to cephaloridine occurred, with increased plasma urea, kidney weight, excretion of urinary enzymes, and kidney lesions. Cephaloridine also increased plasma sorbitol dehydrogenase activity. Selenium deficiency depressed kidney glutathione peroxidase activity (78%) and potentiated cephaloridine nephrotoxicity. Copper deficiency did not increase cephaloridine nephrotoxicity; the small depression (13%) in kidney Cu,Zn-superoxide dismutase activity may not have been sufficient to impair antioxidant status. However, the marked depression in kidney glutathione peroxidase activity during Se deficiency may have impaired antioxidant status and enhanced cephaloridine-induced injury. In contrast to results in the kidney, neither Se deficiency nor Cu deficiency potentiated cephaloridine hepatotoxicity, as assessed by plasma SDH activity.

Changes in Renal Function after Extracorporeal Shock Wave Lithotripsy in Patients with Solitary Functioning Kidneys: Long-Term Follow-Up

Nine of twelve consecutive patients with a solitary functioning kidney treated for renal stone by extracorporeal shock wave lithotripsy (SWL) with the modified Dornier HM3 lithotripter were evaluated before and 20 months (range 12-24 months) after treatment by detailed renal cortical and tubular function tests. Urinary excretion of the renal tubular enzymes N-acetyl-β-glucosaminidase (NAG), alkaline phosphatase (ALP), and kallikrein and of albumin and β2-microglobulin was unchanged. Clearances of creatinine (CCr), inulin (CIN) and para-aminohippuric acid (CPAH) and filtration fraction (FF) were constant, as were serum levels of creatinine, urea, and β2-microglobulin. In seven of the nine patients, however, CIN was decreased at follow-up by a mean of 15% (range 5% to 54%), and CPAH was decreased by a mean of 30% (range 3% to 58%) in six of the nine patients. Plasma renin activity (PRA) and serum aldosterone were stable, and no patient developed new-onset hypertension.

Excretion of Urinary Enzymes after Extracorporeal Shock-Wave Lithotripsy

Journal Article Excretion of Urinary Enzymes after Extracorporeal Shock-Wave Lithotripsy Get access D Cvorisćec, D Cvorisćec Search for other works by this author on: Oxford Academic Google Scholar D Matisić, D Matisić Search for other works by this author on: Oxford Academic Google Scholar A Stavljenić, A Stavljenić Search for other works by this author on: Oxford Academic Google Scholar G Borso G Borso Search for other works by this author on: Oxford Academic Google Scholar Clinical Chemistry, Volume 38, Issue 4, 1 April 1992, Pages 607–608, https://doi.org/10.1093/clinchem/38.4.607 Published: 01 April 1992

Increases in urinary enzyme excretion in rats depleted of glutathione inhibited by scavenger of oxygen free radicals.

Urinary excretion of enzymes by rats was assessed after glutathione (GSH) was depleted by treatment with a mixture of the GSH depletors D,L-buthionine-S,R-sulfoximine (BSO) and diethylmaleate (DEM). Renal GSH was low 2 h after treatment and later returned to the control level. The urinary excretion of gamma-glutamyltranspeptidase (gamma-GTP) and N-acetyl-beta-D-glucosaminidase (NAG) remained high for at least 3 d after the injection of BSO (100 mg/kg) and DEM (0.5 ml/kg), with no effect on the blood urea nitrogen level. N,N'-Dimethylthiourea (DMTU), a scavenger of oxygen free radicals, inhibited this increase in the urinary excretion of gamma-GTP. DMTU also inhibited the increase in cisplatin-induced NAG excretion caused by the GSH depletors. These results suggested that the urinary excretion of these enzymes is an index of renal tubular injury caused by short-term depletion of renal GSH, and that the generation of free radicals may be involved in renal tubular injury during GSH depletion or caused by cisplatin together with GSH depletors.

Iopentol in patients with chronic renal failure: its effects on renal function and its use as glomerular filtration rate parameter.

Iopentol (mean dose 0.42 g I kg-1) was administered for abdominal aortography and pelvic angiography in 10 patients with advanced non-diabetic chronic renal failure (S-creatinine 672 +/- 259 mumol l-1, mean +/- SD). Renal glomerular function measured as creatinine clearance and plasma clearance of [99Tcm]-diethyl-enetriaminepentaacetic acid (DTPA) was unchanged by iopentol, as also was urinary excretion of the renal tubular enzymes N-acetyl-beta-glucosaminidase (NAG) and alkaline phosphatase (ALP). The elimination of iopentol from serum and urine was delayed, and detectable serum and urine concentrations were found 5 days after administration of the contrast medium. Creatine clearance was 47% higher than the corresponding renal iopentol clearance. Plasma iopentol clearance, measured as the total area under the plasma concentration curve, was 40% higher than renal iopentol clearance because of extrarenal elimination of iopentol. We conclude that abdominal aortography with iopentol can be performed without effects on renal glomerular or tubular function parameters in patients with advanced renal failure. If iopentol is used for measurement of glomerular filtration rate (GFR) in this group of patients, one should measure renal clearance, as plasma clearance overestimates GFR.

Quantitative assessment of urinary protein and enzyme excretion--a diagnostic programme for the detection of renal involvement in type I diabetes mellitus.

In an effort to establish a reliable programme for the clinical monitoring of renal involvement in patients with type-I diabetes mellitus, we quantified the urinary excretion of immunoglobulin G (IgG), transferrin (Tf), albumin (Alb), alpha 1-microglobulin (alpha 1MG), N-acetyl-beta-D-glucosaminidase (NAG), and total protein in 130 dipstick negative children and young adults with type-I diabetes. Eighty-five sex- and age-matched healthy persons served as a control group for the definition of the upper reference limits (95th centiles; micrograms min-1 1.73 m2): transferrin 1.4; albumin 16.6; total protein 27.1; NAG: 2.0 mU min-1 1.73 m2. Sex-related differences were detected for IgG (men: 3.8; women: 1.7) and alpha 1 MG (men: 6.0; women: 4.0 micrograms min-1 1.73 m2). The urinary excretion of IgG, Tf, alpha 1MG, NAG, and total protein was significantly higher in subjects with diabetes when compared to healthy controls (p < 0.01). Furthermore, 20 patients (15%) showed an elevated excretion of tubular markers (alpha 1MG and NAG), and 3 patients (2%) of at least two glomerular markers (Alb and/or Tf and/or IgG). Additionally, 18 individuals (14%) presented a mixed excretion pattern of both tubular and glomerular markers. These data suggest that the quantitation of both glomerular and tubular proteinuria provides a sensitive and cost-effective instrument for the non-invasive screening for renal involvement in patients with diabetes mellitus.

Acute Hyperoxaluria, Renal Injury and Calcium Oxalate Urolithiasis

Single intraperitoneal injections of three, seven, or 10 mg. of sodium oxalate per 100 gm. of rat body weight were administered to male Sprague-Dawley rats. At various times after the injection, urine samples were analyzed for oxalate, and urinary enzymes, alkaline phosphatase, leucine aminopeptidase, gamma-glutamyl transpeptidase, and N-acetyl-beta-glucosaminidase. The kidneys were processed for light microscopy and renal calcium and oxalate determination. Oxalate administration resulted in an increase in urinary oxalate and formation of calcium oxalate crystals in the kidneys. The amount and duration of urinary excretion of excess oxalate and retention of crystals in the kidneys correlated with the dose of sodium oxalate administered. At a low oxalate dose of three mg./100 gm., crystals moved rapidly down the nephron and cleared the kidneys. At higher doses crystals were retained in kidneys and at a dose of 10 mg./100 gm. were still there seven days post-injection. Crystal retention was associated with enhanced excretion of urinary enzymes indicating renal tubular epithelial injury.

Urinary excretion of proteins and enzymes in workers exposed to hydrocarbons in a shoe factory

A cross-sectional study was conducted to determine whether exposure to hydrocarbons in a shoe factory may produce renal effects that can be detected by determination of the urinary excretion of proteins and enzymes. The study population included 59 women who had been exposed to petroleum naphtha and toluene and 24 age-matched control women. The time-weighted average exposure to petroleum naphtha, toluene and ethylacetate was 1,619,81 and 160 mg/m3, respectively. The integrity of the renal structures or functions was assessed by measuring the urinary excretion of total protein, beta 2-microglobulin, retinol-binding protein, albumin, transferrin, lysozyme, lactate dehydrogenase and beta-N-acetylglucosaminidase (NAG). The only parameter that was significantly influenced by hydrocarbon exposure was the urinary activity of beta-N-acetylglucosaminidase. Although the health significance of this renal change, which was not accompanied by changes in the urinary excretion of low- or high-molecular-weight proteins, is unclear, the results of the present study are in agreement with our previous observations suggesting that long-term moderate exposure to solvents does not entail a significant risk for the development of nephrotoxicity.

Renal tolerance for ioxaglate in patients with chronic renal failure.

The authors sought to evaluate renal tolerance for ioxaglate sodium meglumine used as a contrast agent in patients with chronic renal failure. Eight male patients (mean age, 55 years +/- 5) with chronic renal insufficiency (glomerular filtration rate less than 60 mL/min) who underwent diagnostic cardiac catheterization were enrolled. Renal clearance of inulin and rho-aminohippuric acid and urinary enzyme excretion were studied 1 day before and 1 day after administration of 167 mL +/- 43 of ioxaglate. None of the patients experienced any adverse reactions. All the patients had markedly depressed renal clearance values before angiography. Mean serum creatinine level, glomerular filtration rate, effective renal plasma flow, and urinary beta 2-microglobulin excretion were unaltered by angiography. After the procedure, only one patient had an increase in serum creatinine level of more than 10% (from 115 to 159 mumol/L [1.3 to 1.8 mg/dL]), with a decrease in glomerular filtration rate from 34 to 27 mL/min. In this patient, serum creatinine level and glomerular filtration rate normalized within 72 hours. Using accurate and sensitive renal function tests, the authors have shown that ioxaglate may be used safely in patients with chronic renal failure.

Biochemical response to cadmium

Dose- and time-related effects of Cd (II) (0.5 or 1.0 mg/kg, Cd as CdCl2.H2O, subcutaneously, daily for 48 h, 1, 3, or 6 wk) were investigated in rats. A dose-related increase in the activity of plasma alkaline phosphatase (ALP), lactate dehydrogenase (LDH), aspartate aminotransferase (GOT), and alanine aminotransferase (GPT) was evident only at 6 wk, whereas an early rise in ALP and LDH was seen at 3 wk in 1.0 mg Cd group only. The hepatic and renal metallothionein (MT) induction displayed a dose- as well as time-related increase with Cd accumulation. A significant increase in hepatic Zn and renal Cu, no change in hepatic Cu, and a slight increase in renal Zn was observed. Urinary ALP and leucine aminopeptidase (LAP) showed an initial increase at 48 h, thereafter returned to near normal. A second phase of enzymuria (ALP, LAP, GOT, GPT, gamma-glutamyl transpeptidase), proteinuria, and aminoaciduria occurred at 6 wk in a dose-related manner. The urinary excretion of specific renal enzymes appeared closely related to the MT induction and organ Cd levels.

Effects of Isradipine on Renal Function in Cydosporin-Treated Renal Transplanted Patients

The renal effects of the calcium-channel antagonist isradipine were evaluated in cyclosporin A (CsA)-treated renal allografted patients more than 5 months after transplantation. Twelve patients with stable renal function were given placebo for 2 weeks and then isradipine 1.25 mg x 2 for 1 week and 2.5 mg x 2 for the next 3 weeks in an open trial. The CsA dose was unchanged during the study. Isradipine did not interfere with the pharmacokinetics of CsA as both whole blood trough and peak levels were unchanged. Isradipine reduced mean arterial blood pressure (MAP) from 117.0 +/- 1.8 to 106.3 +/- 1.9 mmHg (P less than 0.01). The renal effects were studied during water diuresis 1-3 h after drug intake. Para-aminohippurate clearance (CPAH) increased from 256.4 +/- 21.5 to 291.5 +/- 26.3 ml/min (P less than 0.05), renal vascular resistance was reduced by 21.5% (P less than 0.01) and inulin clearance (CIn) was unchanged. Fractional proximal reabsorption, calculated from lithium clearance (CLi), was reduced by 11.9% (P less than 0.01) by isradipine. Isradipine also reduced proximal reabsorption of sodium (APRNa) and increased distal sodium delivery (DDNa). Distal sodium reabsorption (ADRNa) and free-water clearance (CH2O) were significantly increased. Urinary excretion of enzymes and proteins was unchanged by isradipine.

Excretion of Urinary Enzymes in Female Sprague-Dawley Rats in Relation to Cellular Compartment, Creatinine Excretion and Diuresis

One hundred and one young-adult female Sprague-Dawley rats were acclimatized to metabolic cages for 2 days. After that time 24-hour urine was collected at a constant cooling temperature of 0-4 degrees C. After gel filtration the enzyme activities were determined, and the resulting values were used to calculate 24-hour excretions. The following reference ranges (2.5 and 97.5 percentiles) were determined (in mU/24 h): lactate dehydrogenase 43-181; phosphohexoseisomerase 45-1445; glutathione-S-transferase 1-299; alkaline phosphatase 27-1239; leucine arylamidase 72-377; gamma-glutamyltransferase 1334-9188; arylsulphatase A 59-309; beta-galactosidase 76-305; beta-glucuronidase 20-2756; beta-N-acetyl-D-glucosaminidase 66-491; glutamate dehydrogenase 7-711. There was a significant (though not very high) correlation with diuresis for the lysosomal enzymes beta-N-acetyl-D-glucosaminidase, arylsulphatase A and beta-galactosidase, and for glutamate dehydrogenase, lactate dehydrogenase, phosphohexoseisomerase and alkaline phosphatase. The relation to creatinine excretion was markedly close for the lysosomal enzymes beta-N-acetyl-D-glucosaminidase, arylsulphatase A and beta-galactosidase (r = 0.71-0.83), as well as for alkaline phosphatase, leucine arylamidase and gamma-glutamyltransferase. There was a relatively high correlation between the excretion of beta-N-acetyl-D-glucosaminidase, arylsulphatase A and beta-galactosidase among themselves (r = 0.63-0.81) as well as between leucine arylamidase and gamma-glutamyltransferase (r = 0.75).

Assessment of chemotherapy-associated nephrotoxicity in children with cancer

Assessment of the toxicity caused by chemotherapy in children with cancer has become more important as the number of long-term survivors has continued to increase. It is vital to monitor both acute life-threatening adverse effects and long-term toxicity that may impair the child's development and cause permanent morbidity. Renal damage may follow treatment with cytotoxic drugs, especially cisplatin or ifosfamide, and lead to glomerular, proximal tubular or distal tubular impairment or to any combination of these. Greater understanding of nephrotoxicity and of its prevention may enable the use of more intensive schedules or of higher doses of potentially nephrotoxic chemotherapy. However, the evaluation of cytotoxic drug-induced nephrotoxicity has frequently depended mainly on measurement of the plasma creatinine concentration, which may remain normal despite substantial glomerular impairment or severe tubular dysfunction. Detailed assessment of nephrotoxicity depends on an understanding of normal renal physiology and requires evaluation of all aspects of function. A comprehensive but simple investigatory protocol that enables assessment of the nature and severity of nephrotoxicity in children is described, which can be performed without admission to hospital. Glomerular function is assessed by measurement of the glomerular filtration rate from the plasma clearance of [51Cr]-ethylenediaminetetraacetic acid ([51Cr]-EDTA). Proximal nephron function is evaluated in three ways: by measurement of the concentration of calcium, magnesium, phosphate, glucose and urate in blood and urine along with calculations of their fractional excretion and of the renal threshold for phosphate; by determination of the excretion in urine of low-molecular-weight proteins (e.g. retinol-binding protein); and by investigation of urinary bicarbonate excretion in patients who are acidotic. Distal nephron function is initially investigated by examination of the concentration (osmolality) and acidification (pH) of an early morning sample of urine. Finally, a group of general investigations is performed, including quantitation of urinary excretion of renal tubular enzymes (e.g. N-acetylglucosaminidase) and measurement of blood pressure.

103 Urinary protein and enzyme excretion in pre-eclampsia

103 Urinary protein and enzyme excretion in pre-eclampsia

Investigations on the acute and chronic nephrotoxicity of the new platinum analogue carboplatin

In order to detect even subclinical hints of nephrotoxicity after application of carboplatin, sensitive non-invasive methods, e.g. determination of urinary enzyme (lactate dehydrogenase, leucine aminopeptidase, gamma-glutamyltransferase, N-acetyl-beta-glucosaminidase), glomerular and tubular protein excretion (albumin, alpha-1-microglobulin) and determination of the creatinine clearance, were used. Eighteen patients with small-cell lung cancer entered the study. All patients were treated with the three-drug combination chemotherapy: vincristine (1.5 mg i.v. on days 1, 8, 15, 22), etopside (escalating doses: 100-160 mg/m2 on days 1-3) and carboplatin (300 mg/m2 day 1). Investigations were made during the first, third and fifth treatment cycles. Deterioration of renal function occurred in 4 out of 18 patients in all three observed treatment courses. Abnormal amounts in the excretion of at least one of four urinary enzymes were found in 6 out of 18 patients during the first cycle and in 4 out of 8 patients during the third and fifth cycles. All patients with pathological enzymuria during the first treatment course also developed an increased enzymuria during cycles 3 and 5. Four patients developed pathological proteinuria during the first and 2 patients during the third and fifth cycles. These findings demonstrate that the new platinum analogue, carboplatin, is capable of inducing renal damage. In comparison with cisplatinum, the nephrotoxicity of this new analogue is reduced but not completely eliminated.

Assessment of renal function: selected developments

Tests commonly used to assess the glomerular filtration rate (GFR) and to detect renal tubular damage are critically reviewed. Creatinine clearance which is frequently used for assessment of the GFR is prone to several errors. The plasma creatinine can be used to provide a rough guide but for reliable measurement of the GFR, 51Cr-EDTA clearance is recommended. Measurements of the urinary excretion of low molecular weight proteins, enzymes and kidney tissue proteins have been used to detect tubular damage. Of the low molecular weight proteins excreted, beta-2-microglobulin is unstable and measurement of retinol-binding protein or alpha-1-microglobulin is recommended for the detection of chronic renal tubular malfunction. Of the many enzymes that have been studied, urinary N-acetyl-beta-D-glucosaminidase or alanine aminopeptidase are recommended as being the most useful for the early detection of acute renal tubular damage. Among renal tissue proteins that have been measured in urine adenosine-deaminase-binding protein, a tubular brush border antigen appears to have considerable potential for providing early warning of renal allograft rejection.

Urinary Enzyme Excretion after Donor Nephrectomy – How Should We Express and Compare Excretion Rates of the Remaining Kidney after Donor Nephrectomy?

Urinary Enzyme Excretion after Donor Nephrectomy – How Should We Express and Compare Excretion Rates of the Remaining Kidney after Donor Nephrectomy?

Excretion of urinary enzymes after extracorporeal shock-wave lithotripsy.

Excretion of urinary enzymes after extracorporeal shock-wave lithotripsy.

Selective Elevation of Urinary Enzyme Levels after Extracorporeal Shock Wave Lithotripsy

Urinary enzyme testing has been used by many investigators to diagnose and monitor various types of renal injury. Three urinary enzymes, N-acetyl-beta-glucosaminidase, beta-galactosidase and gamma-glutamyl transferase were monitored in 17 patients before and after a single, unilateral extracorporeal shock wave lithotripsy treatment. Stones were in the renal pelvis or calices except for 1 treated in situ in the proximal ureter. Urine specimens were collected before extracorporeal shock wave lithotripsy and at 1, 3, 5, 7, 10, 14, 21 and 28 days after treatment. N-acetyl-betaglucosaminidase and beta-galactosidase levels increased significantly after treatment (p less than 0.05). Gamma-glutamyl transferase levels increased after treatment but this was not statistically significant. All enzyme levels were highest on days 1 and 3 after lithotripsy and returned to baseline by day 28. Factors associated with post-treatment enzyme elevation included female sex, a lower pre-treatment creatinine clearance and stone size greater than 1cm. These findings indicate that there is a transient selective increase in urinary enzyme excretion after extracorporeal shock wave lithotripsy.