Technetium‐99m‐MAG3 and technetium‐99m‐DTPA: Renal clearance measured by the constant infusion technique – Old news?

2021 ◽  
Vol 41 (6) ◽  
pp. 488-496
Author(s):  
Ann Mai Østergaard ◽  
Stine S. Langaa ◽  
Marie H. Vrist ◽  
Frank H. Mose ◽  
Jesper N. Bech ◽  
...  
Keyword(s):  
Renal Clearance ◽  
Constant Infusion ◽  
Technetium 99M ◽  
Infusion Technique

Renal Clearance of [14C]oxalate: Comparison of Constant-Infusion with Single-Injection Techniques

1982 ◽  
Vol 63 (1) ◽  
pp. 47-51 ◽  
Author(s):  
J. A. C. Prenen ◽  
P. Boer ◽  
E. J. Dorhout Mees ◽  
H. J. Endeman ◽  
S. M. Spoor ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Renal Clearance ◽  
Single Injection ◽  
Compartment Model ◽  
Constant Infusion ◽  
Injection Technique ◽  
Clearance Ratio ◽  
Urine Sampling ◽  
Two Compartment Model ◽  
Infusion Technique

1. The renal clearance of [14C]oxalate was assessed by the constant-infusion technique and single-injection technique (plasma sampling only: one-compartment and two-compartment model; plasma and urine sampling). Healthy volunteers and patients with renal stones were studied. 2. Results with the constant-infusion techniques (with and without urine sampling) were not significantly different from each other. 3. The renal clearance of [14C]oxalate measured with the single-injection technique as compared with the constant-infusion technique was overestimated in the single-injection one-compartment model (52%) as well as in the two-compartment model (30%). 4. The calculated level of plasma oxalate in the healthy volunteers ranged from 1·04 to 1·78 μmol/l (mean 1·39). 5. The biological half-life of [14C]oxalate, estimated by the cumulative excretion of 14C in urine after equilibrium had been established, was 128 min (range: 113–142). 6. The oxalate/creatinine clearance ratio in the healthy volunteers ranged from 1·73 to 2·22 (mean 2·01).

A Comparative Study on the Metabolism of Human Insulin and Porcine Proinsulin in Man

1973 ◽  
Vol 45 (5) ◽  
pp. 633-654 ◽  
Author(s):  
P. H. Sönksen ◽  
Christine V. Tompkins ◽  
M. C. Srivastava ◽  
J. D. N. Nabarro
Keyword(s):  
Human Insulin ◽  
Normal Subjects ◽  
Constant Infusion ◽  
Metabolic Clearance ◽  
Priming Dose ◽  
Metabolic Clearance Rate ◽  
Serum Growth Hormone ◽  
Biological Potency ◽  
Infusion Technique ◽  
Apparent Distribution

1. The metabolism of unlabelled monocomponent human insulin and porcine proinsulin was studied in ten normal subjects (five males and five females) by using a priming dose-constant-infusion technique. In each subject, the metabolic clearance rate (MCR) was measured at four separate steady-state hormone concentrations averaging 16–216 μunits/ml (insulin) and 4·2–42·8 ng/ml (proinsulin). 2. For insulin the MCR fell progressively from 34 ml kg−1 min−1 at a mean fasting insulin concentration of 3·8 μunits/ml to 11·4 ml kg−1 min−1 at the highest concentration achieved (280 μunits/ml); for proinsulin MCR averaged 3·7 ml kg−1 min−1 at a mean plasma concentration of 4·2 ng/ml and fell to 2·71 ml kg−1 min−1 at 10·7 ng/ml, remaining constant thereafter at concentrations up to 71 ng/ml. 3. The half-disappearance time (T½) from the plasma, after the end of the infusion, averaged 4·3 min for insulin and 25·6 min for proinsulin. 4. The apparent distribution space (DS) was similar for both hormones (83 ml/kg of insulin and 98·9 ml/kg of proinsulin). 5. There was a direct correlation between T½ and DS for both hormones. 6. Although the higher MCR of insulin was reflected in its shorter T½ there was, for each hormone, no relationship between MCR and T½. 7. The biological potency of porcine proinsulin, as judged by its effect on plasma glucose, was approximately 5% of that of insulin. 8. The responses of serum growth hormone and Cortisol were shown to be directly related to the degree of hypoglycaemia induced.

Assessment of methods for improving tracer estimation of non-steady-state rate of appearance

1999 ◽  
Vol 87 (5) ◽  
pp. 1813-1822 ◽  
Author(s):  
A. Gastaldelli ◽  
A. R. Coggan ◽  
R. R. Wolfe
Keyword(s):  
Steady State ◽  
Infusion Rate ◽  
Traditional Approach ◽  
Volume Of Distribution ◽  
Constant Volume ◽  
Constant Infusion ◽  
Steady State Condition ◽  
Fixed Volume ◽  
The One ◽  
Infusion Technique

The most common approach for estimating substrate rate of appearance (Ra) is use of the single-pool model first proposed by R. W. Steele, J. S. Wall, R. C. DeBodo, and N. Altszuler. ( Am. J. Physiol. 187: 15–24, 1956). To overcome the model error during highly non-steady-state conditions due to the assumption of a constant volume of distribution (V), two strategies have been proposed: 1) use of a variable tracer infusion rate to minimize tracer-to-tracee ratio (TTR) variations (fixed-volume approach) or 2) use of two tracers of the same substrate with one infused at a constant rate and the other at a variable rate (variable-volume approach or approach of T. Issekutz, R. Issekutz, and D. Elahi. Can. J. Physiol. Pharmacol. 52: 215–224, 1974). The goal of this study was to compare the results of these two strategies for the analysis of the kinetics of glycerol and glucose under the non-steady-state condition created by a constant infusion of epinephrine (50 ng ⋅ kg−1 ⋅ min−1) with the traditional approach of Steele et al., which uses a constant infusion and fixed volume. The results showed that for glucose and glycerol the estimates of Raobtained with the constant and the variable tracer infusion rate and the equation of Steele et al. were comparable. The variable tracer infusion approach was less sensitive to the choice of V in estimating Ra for glycerol and glucose, although the advantage of changing the tracer infusion rate was greater for glucose than for glycerol. The model of Issekutz et al. showed instability when the ratio TTR1/TTR2approaches a constant value, and the model is more sensitive to measurement error than the constant-volume model for glucose and glycerol. We conclude that the one-tracer constant-infusion technique is sufficient in most cases for glycerol, whereas the one-tracer variable-infusion technique is preferable for glucose. Reasonable values for glucose Ra can be obtained with the constant-infusion technique if V = 145 ml/kg.

P.22 Taurine kinetics assessed with [1,213C2] taurine in humans: comparison of bolus injection versus constant infusion technique

1998 ◽  
Vol 17 ◽  
pp. 35
Author(s):  
B. Rakotoambinina ◽  
F. Iglicki ◽  
L. Marks ◽  
P. Crenn ◽  
F. Thuillier ◽  
...  
Keyword(s):  
Bolus Injection ◽  
Constant Infusion ◽  
Infusion Technique

Diodrast (I131) whole blood clearance as an index of renal blood flow

1964 ◽  
Vol 206 (2) ◽  
pp. 309-312 ◽  
Author(s):  
Harry A. Fozzard
Keyword(s):  
Blood Flow ◽  
Renal Blood Flow ◽  
Correlation Coefficient ◽  
Intravenous Injection ◽  
Whole Blood ◽  
Constant Infusion ◽  
Urine Collection ◽  
Blood Clearance ◽  
Single Intravenous Injection ◽  
Infusion Technique

The whole blood clearance of Diodrast (I131) following a single intravenous injection was used to estimate renal blood flow. This method was compared to renal blood flow simultaneously determined by the PAH constant infusion technique. A correlation coefficient of 0.930 was found. The Diodrast clearance method is recommended because it is simple and rapid, and it avoids the necessity for urine collection.

Arginine vasopressin metabolism in dogs. I. Evidence for a receptor-mediated mechanism.

1978 ◽  
Vol 235 (6) ◽  
pp. E591 ◽  
Author(s):  
R E Weitzman ◽  
D A Fisher
Keyword(s):  
Arginine Vasopressin ◽  
Urine Osmolality ◽  
Volume Of Distribution ◽  
Membrane Receptors ◽  
Constant Infusion ◽  
Metabolic Clearance ◽  
Strong Negative Correlation ◽  
Pulse Injection ◽  
Plasma Membrane Receptors ◽  
Infusion Technique

The plasma clearance rates (PCR) of arginine vasopressin (AVP), and iodinated AVP (125I-AVP) were determined after pulse injection in conscious water-loaded dogs. Both the PCR and the apparent initial volume of distribution were significantly greater for AVP than for the biologically inactive iodinated AVP 37.4 +/- 4.8 ml/kg per min vs. 6.7 +/- 0.8 ml/kg per min (P less than 0.001) and 12.7 +/- 0.9% body wt vs. 7.1 +/- 0.4% body wt (P less than 0.001). AVP clearance was then determined by the constant-infusion technique at doses that produced equilibrium AVP concentrations within and above the physiological range. AVP-PCR was 37.4 +/- 7.1 ml/kg per min at 34 microU/kg per min, which was comparable to that after pulse injection (P less than 0.9). AVP clearance fell progressively, and urine osmolality progressively increased with increasing AVP infusion rates to plateau values at 136 microU/kg per min; a strong negative correlation was observed between mean AVP-PCR and urine osmolality (r = -0.993). The data suggest a relationship between the biological activity of AVP and its clearance. It is proposed that plasma membrane receptors may mediate a portion of the metabolic clearance of AVP.

Secretory dynamics of 1α-hydroxycorticosterone in the elasmobranch fish, Scyliorhinus canicula

1984 ◽  
Vol 103 (2) ◽  
pp. 205-211 ◽  
Author(s):  
N. Hazon ◽  
I. W. Henderson
Keyword(s):  
Sodium Chloride ◽  
Sea Water ◽  
Specific Activity ◽  
Plasma Concentrations ◽  
High Specific Activity ◽  
Constant Infusion ◽  
Metabolic Clearance ◽  
Plasma Osmolarity ◽  
Scyliorhinus Canicula ◽  
Infusion Technique

ABSTRACT Peripheral plasma concentrations, metabolic clearance rates (MCR) and blood production rates (BPR) of 1α-hydroxycorticosterone (1-OH-B) were determined in female dogfish (Scyliorhinus canicula) under varying environmental conditions. The constant-infusion technique, using high specific activity tritiated 1-OH-B, was applied to measure the MCR, and BPR were derived from the product of plasma concentration and MCR at equilibrium. Urea plasma clearances and apparent BPR were assessed in a similar manner. Fish were adapted stepwise to 140, 120, 90, 80, 70, 60 and 50% normal sea water (about 1000 mosmol/l). In all cases 1-OH-B was the major corticosteroid, cortisol and corticosterone were sought but never detected. In environments of reduced osmolarity, plasma osmolarity, sodium, chloride and urea concentrations all declined, alongside increases in plasma concentrations, MCR and BPR of 1-OH-B. In fish held in environments at concentrations greater than normal sea water, plasma osmolarity, sodium, chloride and urea concentrations all increased. Plasma clearance of urea increased in fish held in environments more dilute than sea water, while it decreased in the more hyperosmotic waters. It is tentatively concluded that homeostasis of plasma composition, with particular respect to urea, is in part regulated by 1-OH-B in the dogfish. J. Endocr. (1984) 103, 205–211

Novel Polar Single Amino Acid Chelates for Technetium-99m Tricarbonyl-Based Radiopharmaceuticals with Enhanced Renal Clearance: Application to Octreotide

2010 ◽  
Vol 21 (6) ◽  
pp. 1032-1042 ◽  
Author(s):  
Kevin P. Maresca ◽  
John C. Marquis ◽  
Shawn M. Hillier ◽  
Genliang Lu ◽  
Frank J. Femia ◽  
...  
Keyword(s):  
Amino Acid ◽  
Renal Clearance ◽  
Single Amino Acid ◽  
Technetium 99M
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