Creatinine Secretion by the Frog Renal Tubule

1956 ◽  
Vol 184 (3) ◽  
pp. 527-534 ◽  
Author(s):  
Robert E. Swanson
Keyword(s):  
Sodium Azide ◽  
Sodium Arsenite ◽  
Renal Tubule ◽  
Inulin Clearance ◽  
Clearance Ratio ◽  
Creatinine Concentration ◽  
Urinary Creatinine ◽  
Intact Kidney

Simultaneous creatinine and inulin clearance measurements were carried out in Ringer-perfused and intact kidneys of the bullfrog ( R. catesbiana). For the perfusion series the median creatinine/inulin clearance ratio was 1.27. The ratio was elevated above unity for the majority of intact kidney experiments. Perfusion with poisons such as phlorizin, sodium azide, sodium arsenite and 2, 4-dinitrophenol, as well as elevation of the creatinine concentration in perfusing fluids, generally depressed the clearance ratio toward unity. It is concluded that a portion of the urinary creatinine of bullfrogs can be excreted by active tubular participation.

Stop-flow analysis of creatinine excretion in the dog

1962 ◽  
Vol 203 (6) ◽  
pp. 980-984 ◽  
Author(s):  
Robert E. Swanson ◽  
Ali A. Hakim
Keyword(s):  
Creatinine Clearance ◽  
Competitive Inhibition ◽  
Flow Analysis ◽  
High Plasma ◽  
Free Flow ◽  
Inulin Clearance ◽  
Plasma Creatinine ◽  
Clearance Ratio ◽  
Creatinine Concentration ◽  
Stop Flow

Urinary excretion patterns of creatinine and inulin under stop-flow conditions in male mongrel dogs were compared. Evidence for a weak creatinine secretory mechanism at the proximal tubule level include the following: 1) Exogenous creatinine in the stop-flow samples appears prior to inulin when both are injected midway during a 10-min ureteral clamping period. 2) The ratio of creatinine/inulin U/P values (creatinine clearance ratio) shows a peak and a distribution coextensive with PAH/inulin clearance ratios. 3) Self-depression of the peak stop-flow creatinine clearance ratio was obtained at high plasma creatinine concentrations. 4) High plasma p-aminohippuric acid levels depressed the free-flow and peak stop-flow creatinine clearance ratios and, conversely, high plasma creatinine concentration depressed free-flow and peak stop-flow PAH clearance ratios (competitive inhibition). 5) Probenecid reduced free-flow and peak stop-flow creatinine clearance ratios (creatinine secretory mechanism blocked). The mean free-flow creatinine/inulin clearance ratios in 44 clearance periods was 1.2±0.1 (sd), compared to the peak stop-flow ratio of 1.8±0.4 (sd) (N = 20) at plasma creatinine concentrations less than 20 mg/100 ml.

Renal Injury in Sick Newborn Infants: A Prospective Evaluation Using Urinary β2-Microglobulin Concentrations

PEDIATRICS ◽  
1988 ◽  
Vol 81 (3) ◽  
pp. 432-440
Author(s):  
Eric D. Tack ◽  
Jeffrey M. Perlman ◽  
Alan M. Robson ◽  
Cathy Hausel ◽  
Charles C. T. Chang
Keyword(s):  
Renal Injury ◽  
Confidence Limit ◽  
Newborn Infants ◽  
Tubular Injury ◽  
Creatinine Concentration ◽  
Term Infants ◽  
Urinary Creatinine ◽  
Β2 Microglobulin ◽  
Sick Newborn ◽  
Healthy Infants

Urinary concentrations of β2-microglobulin and creatinine were measured serially in 140 sick infants, of whom 109 were asphyxiated, and in 35 healthy preterm and term infants. First voided urines and samples from days 3 and 7 postpartum were studied. Urinary β2-microglobulin concentrations in healthy infants averaged 1.34 ± 1.34 mg/L (mean ± SD) in first voided specimens and 1.32 ± 0.98 mg/L in day 3 samples; the calculated upper limit of normal (95% confidence limit) was 4.00 mg/L. Elevated values (those exceeding the 95% confidence limit) occurred most often in the sick asphyxiated patients (56%); the first voided sample value in these patients was 10.0 ± 10.4 mg/L. The equivalent value in the sick nonasphyxiated infants was 8.32 ± 7.27 mg/L. Values were significantly and persistently elevated in the sick infants on days 3 and 7. Factoring β2-microglobulin levels by urinary creatinine concentration did not affect the significance of the findings. The increased urinary β2-microglobulin levels were not (1) related to gestational age; low β2-microglobulin values occurred at all gestational ages for both healthy and sick infants; (2) a consequence of urine flow rate; urinary β2-microglobulin did not correlate with urinary creatinine concentration or with urine to plasma creatinine ratio; and (3) a consequence of increased production of β2-microglobulin; urinary and serum β2-microglobulin values did not correlate (r = .03). Thus, we propose that the elevated levels of urinary β2-microglobulin in the sick infants were the consequence of tubular injury. This was associated with hematuria but not with a high incidence of azotemia or oliguria. In the most premature infants (<32 weeks), elevated urinary β2-microglobulin concentrations were associated with significantly increased urinary concentrations of sodium and potassium. These data suggest a higher prevalence of acute tubular injury in sick newborn infants than has been reported in previous studies in which more traditional indices of renal injury were used.

scholarly journals Nutritional and Non-Nutritional Predictors of Low Spot Urinary Creatinine Concentration in Patients with Heart Failure

Nutrients ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 3994
Author(s):  
Jolanta Malinowska-Borowska ◽  
Aleksandra Kulik ◽  
Marta Buczkowska ◽  
Weronika Ostręga ◽  
Apolonia Stefaniak ◽  
...  
Keyword(s):  
Risk Factors ◽  
Heart Failure ◽  
Weight Loss ◽  
Creatinine Concentration ◽  
Urinary Creatinine ◽  
Under Nutrition ◽  
Patients With Heart Failure ◽  
Poor Outcomes ◽  
Biochemical Indices ◽  
Appendicular Muscle Mass

Low spot urinary creatinine concentration (SUCR) is a marker of muscle wasting and clinical outcome. The risk factors for low SUCR in heart failure (HF) remain poorly understood. We explored the risk factors for low SUCR related to poor outcomes. In 721 HF patients (age: 52.3 ± 11 years, female: 14%, NYHA: 2.7 ± 0.7) SUCR and Dexa body composition scans were performed. BMI prior HF-onset, weight loss, and appendicular muscle mass were obtained. Each patient was classified as malnutrition or normal by GLIM criteria and three other biochemical indices (CONUT, PNI, and GRNI). Sarcopenia index (SI) as creatinine to cystatin C ratio was also calculated. Within 1 year, 80 (11.1%) patients died. In ROC curve we identified a SUCR value of 0.628 g/L as optimally discriminating surviving from dead. In low SUCR group more advanced HF, higher weight loss and catabolic components of weight trajectory (CCWT), more frequent under-nutrition by GLIM, and lower SI were observed. In multivariate analysis the independent predictors of low SUCR were SI, CCWT, and GNRI score. In conclusion: the risk of low SUCR was associated with a worse outcome. Low SUCR was associated with greater catabolism and sarcopenia but not with biochemical indices of malnutrition.

Root Absorption and Translocation of Picloram by Oats and Soybeans

Weed Science ◽  
1971 ◽  
Vol 19 (6) ◽  
pp. 727-731 ◽  
Author(s):  
A. R. Isensee ◽  
G. E. Jones ◽  
B. C. Turner
Keyword(s):  
Glycine Max ◽  
Plant Species ◽  
Sodium Azide ◽  
Avena Sativa ◽  
Sodium Arsenite ◽  
Solution Concentration ◽  
Metabolic Inhibitors ◽  
Root Absorption ◽  
Soybean Roots ◽  
Initial Uptake

The effects of time, concentration, pH, temperature, and metabolic inhibitors on 4-amino-3,5,6-trichloropicolinic acid (picloram) uptake from nutrient solution by oats (Avena sativaL. ‘Markton’) and soybeans (Glycine maxL. ‘Lee’) were studied. Oats and soybeans had similar absorption patterns of rapid initial uptake. However, total accumulation patterns markedly differed in that accumulation was concentration-dependent for oats but not for soybeans. Initial uptake by oats and soybean roots increased as solution concentration increased. Picloram was redistributed in oats and soybeans and some egress from roots to solution occurred. Picloram uptake by both plant species was markedly diminished with an increase in pH from 3.5 to 4.5, but pH had little effect from 4.5 to 9.5. Less picloram was taken up by oats and soybean roots from solution maintained at 4 C than at 26 C. Translocation to tops followed a similar trend. Increasing concentrations of three metabolic inhibitors, 2,4-dinitrophenol (DNP), sodium azide, and sodium arsenite, reduced root uptake of picloram in both species. All inhibitors (except DNP for oats) at 10−6to 10−5molar concentrations stimulated translocation of picloram to oats and soybean tops while higher concentrations depressed translocation.

How should urinary cotinine concentrations be adjusted for urinary creatinine concentration?

1990 ◽  
Vol 187 (3) ◽  
pp. 289-295 ◽  
Author(s):  
S.G. Thompson ◽  
R.D. Barlow ◽  
N.J. Wald ◽  
H. Van Vunakis
Keyword(s):  
Creatinine Concentration ◽  
Urinary Creatinine ◽  
Urinary Cotinine

scholarly journals Reference Values for Urinary HMMA, HVA, Noradrenaline, Adrenaline, and Dopamine Excretion in Children Using Random Urine Samples and HPLC with Electrochemical Detection

1992 ◽  
Vol 29 (4) ◽  
pp. 400-404 ◽  
Author(s):  
M Fitzgibbon ◽  
R J FitzGerald ◽  
W P Tormey ◽  
A O'Meara ◽  
D Kenny
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Electrochemical Detection ◽  
High Performance ◽  
Homovanillic Acid ◽  
Urine Samples ◽  
Age Group ◽  
Creatinine Concentration ◽  
Urinary Creatinine ◽  
Reference Limits

Random urine samples were collected from 305 children aged from birth to 14 years and the values of hydroxymethoxymandelic acid, homovanillic acid, noradrenaline, adrenaline, and dopamine were measured by high-performance liquid chromatography with electrochemical detection. The results were reported relative to the urinary creatinine concentration and the values declined progressively with increasing age for each analyte with the exception of adrenaline. The results for each age group were not normally distributed and all values except outliers were retained in determining the upper reference limits.

Normal limits of urinary excretion of eleven enzymes.

1976 ◽  
Vol 22 (10) ◽  
pp. 1567-1574 ◽  
Author(s):  
D Maruhn ◽  
I Fuchs ◽  
G Mues ◽  
K D Bock
Keyword(s):  
Alkaline Phosphatase ◽  
Lactate Dehydrogenase ◽  
Urinary Excretion ◽  
Gel Filtration ◽  
Reference Intervals ◽  
Creatinine Concentration ◽  
Urinary Creatinine ◽  
Gamma Glutamyltransferase ◽  
Normal Limits ◽  
Alpha Glucosidase

Abstract Urinary excretion of lactate dehydrogenase, hydroxybutyrate dehydrogenase, gamma-glutamyltransferase, alkaline phosphatase, arylsulphatase A, alpha-glucosidase, beta-galactosidase, trehalase, N-acetyl-beta-glucosaminidase, beta-glucuronidase, and leucinearylamidase was studies in a carefully selected group of 100 healthy subjects, 50 women and 50 men. Enzyme activities were assayed in 3-h morning samples after gel filtration of the urine. Activities were related to time volume, and to urinary creatinine concentration. Several transforming functions had to be applied to enzyme output data to obtain an approximation to gaussian frequency distribution. Men showed a significantly higher excretion of gamma-glutamyltransferase, alpha-glucosidase, trehalase, N-acetyl-beta-glucosaminidase,beta-glucuronidase, and leucine arylamidase activity than did women if enzyme activity was related to urinary time volume. Women excreted more lactate dehydrogenase, hydroxybutyrate dehydrogenase, gamma-glutamyltransferase, alkaline phosphatase, alpha-glucosidase, trehalase, and N-acetyl-beta-glucosaminidase activity than did men, if urinary creatinine was used as the basis of reference. Reference intervals were calculated as 2.5 and 97.5 percentiles for both sexes.

Renal function in water snakes

1962 ◽  
Vol 203 (6) ◽  
pp. 995-1000 ◽  
Author(s):  
S. J. LeBrie ◽  
I. D. W. Sutherland
Keyword(s):  
Tubular Secretion ◽  
Urine Flow ◽  
Urinary Concentration ◽  
Clearance Ratio ◽  
Creatinine Concentration ◽  
Plasma Creatinine Concentration ◽  
Tenfold Increase ◽  
Solute Excretion ◽  
Water Snakes ◽  
Filtered Load

Electrolyte and osmolar concentrations of ureteral urine were compared with serum in several species of water snakes. Hyperosmotic urine was never observed, even after 48 hr of water deprivation. This finding is consistent with the countercurrent theory which precludes urinary concentration when Henle's loops are absent, as in reptilian kidneys. The creatinine/inulin clearance ratio may exceed 2.0, suggesting tubular secretion of creatinine. Tubular secretion is further suggested by the fact that the clearance ratio approaches unity when plasma creatinine concentration is elevated. Variations in glomerular activity are reflected in urine flow in snakes as shown by a direct relationship between clearance of inulin (GFR) and urine flow In snakes solute excretion is dependent on an increase in functional tubular population, with a concomitant increase in filtered load and not a decrease in tubular solute reabsorption. Evidence for this concept is presented and indicates that, over a tenfold increase in GFR, snakes continue to excrete about the same per cent of their filtered load. Water reabsorption, on the other hand, appears to be similar in character to that seen in higher vertebrates. Proximally, it appears to be dependent on solute reabsorption ("obligatory"), whereas distally it is influenced by ADH ("facultative").

Assessment of renal function by inulin clearance: comparison with creatinine clearance as determined by enzymatic methods.

1989 ◽  
Vol 35 (2) ◽  
pp. 312-314 ◽  
Author(s):  
F S Apple ◽  
P Benson ◽  
P A Abraham ◽  
T G Rosano ◽  
C E Halstenson
Keyword(s):  
Renal Function ◽  
Glomerular Filtration Rate ◽  
Creatinine Clearance ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
The Other ◽  
Inulin Clearance ◽  
Urinary Creatinine ◽  
Single Slide ◽  
Enzymatic Methods

Abstract We compared creatinine clearances determined by enzymatic (Kodak Ektachem 700 single-slide, Boehringer Mannheim creatinine PAP) and nonenzymatic (Jaffé, HPLC) methods with glomerular filtration rate measured by inulin clearance in patients with varying degrees of renal function. The Kodak enzymatic assay gave values for creatinine 2 to 3 mg/L higher than the other methods. This resulted in significantly lower creatinine clearances than inulin clearances and creatinine clearances determined by the other methods. However, correlations between all methods for serum and urinary creatinine values and clearances were good. To avoid between assay (enzymatic vs nonenzymatic) discrepancies, manufacturers should agree to an acceptable standard of calibration under the usual conditions used with patients.

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