Summary
Clearance experiments were carried out in rats for evaluating the reliability of Inulin-Methoxy-H3 as marker for GFR determination. When H3 Inulin clearance was compared with C14 Polyethylen Glycol (PEG) 1000 clearance, a linear relationship was observed (y=0.021+0.867x;r=0.98).
H3 Inulin clearance/C14 PEG clearance ratio was 0.88±0.09 (S.D.), i.e. a value no different from those reported in literature for unlabeled Inulin, C14 Inulin and Polyfructosan S. Several types of scintillation solution were tested to evaluate the stability with time of count rate of radioactive Inulin. A perfect reproducibility with time was observed in the clearance values in the kidney as a whole (GFR) and in single nephrons (SNGFR) with the following scintillators: Triton X 100-Toluene-PPO, Aquasol and Instagel. Useful suggestions on the way of using labeled Inulin are given.
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Andreucci, V.E., Canton, A.D., Corradi, A. et al. Reliability of radioactive inulin as a marker of glomerular filtration rate in the rat. Pflugers Arch. 350, 347–358 (1974). https://doi.org/10.1007/BF00592643
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DOI: https://doi.org/10.1007/BF00592643