1. Online feedback–controlled renal constant infusion clearances in rats
Daniel Schock-Kusch, Yury Shulhevich, Qing Xie, Juergen Hesser, Dzmitry Stsepankou, Sabine Neudecker, Jochen Friedemann, Stefan Koenig, Ralf Heinrich, Friederike Hoecklin, Johannes Pill, Norbert Gretz 
Kidney International 
Volume 82, Issue 3, Pages (August 2012)
DOI: /ki
Copyright © 2012 International Society of Nephrology Terms and Conditions

2. Figure 1
Simulated constant infusion clearance runs using fixed infusion dose but varying loading doses. Simulated interstitial fluorescence intensity curves based on a fluorescein isothiocyanate-sinistrin (FITC-S) infusion dose of 0.16mg/min per 100g body weight (bw) without (a) and after a loading dose of 5 (b) or 10mg/100g bw FITC-S (c) in rats with different glomerular filtration rate (GFR) conditions (solid lines: healthy Sprague–Dawley, dashed lines: with unilateral nephrectomy, dotted lines: PKD/Mhm rats). Independent of the GFR level, a short equilibration time of 0.5h is obtained when the maintenance dose receives the peak fluorescence signal after loading dose.
Kidney International  , DOI: ( /ki )
Copyright © 2012 International Society of Nephrology Terms and Conditions

3. Figure 2
Simulated constant infusion clearance runs using varying infusion doses and a fixed loading dose. Simulated interstitial fluorescence intensity curves based on a loading dose of 5mg/100g body weight (bw) and followed by a maintenance infusion dose of 0.02 (a), 0.1 (b), 0.2 (c), and 0.4mg/min per 100g bw (d) in rats with different glomerular filtration rate conditions (for more details see Figure 1). Equilibration time is prolonged markedly and varies up to more than 4h depending on the chosen dosing parameters.
Kidney International  , DOI: ( /ki )
Copyright © 2012 International Society of Nephrology Terms and Conditions

4. Figure 3
Optimized constant infusion clearance parameters. Simulation results of fluorescein isothiocyanate-sinistrin loading dose, maintenance infusion dose, and equilibration time (color coded) based on various animal models are depicted (healthy Sprague–Dawley (a), with unilateral nephrectomy (b), and PKD/Mhm rats (c)). Optimal loading dose/maintenance infusion dose ratio for each animal model is clearly identified.
Kidney International  , DOI: ( /ki )
Copyright © 2012 International Society of Nephrology Terms and Conditions

5. Figure 4
Schematic drawing of the regulation loop for constant infusion clearance. Arrangement and basic components are shown, including the fluorescence detector, controller implemented on a host PC for the regulation of the infusion pump, and the compartments of marker distribution such as blood, interstitial fluid (IF), and urine.
Kidney International  , DOI: ( /ki )
Copyright © 2012 International Society of Nephrology Terms and Conditions

6. Figure 5
Exemplary run using the real-time feedback constant infusion clearance system in a Sprague–Dawley (SD) rat. Mean arterial pressure (MAP, a) and fluorescence intensity (b) of a representative continuous infusion clearance experiment run by the real-time feedback system in an anaesthetized SD rat. Fluorescein isothiocyanate-sinistrin loading dose of 4mg/100g body weight (bw) was followed by a steady infusion of 0.015ml/min (10mg/ml). Horizontal line in b marks the chosen fluorescence reference level. Regulation loop starts 40min (vertical line 0) after bolus. BL (baseline), 1h, and 2h indicate time of blood sampling for plasma concentration measurement. Stable conditions are demonstrated by the course of the curves for both parameters during the constant infusion clearance measurement period of 2.5h.
Kidney International  , DOI: ( /ki )
Copyright © 2012 International Society of Nephrology Terms and Conditions