Abstract
Taurine, a β-amino acid, was used as a marker to study the effect of dietary amino acid manipulation on β-amino acid transport by rat renal epithelium. Adult (57-58 day old) rats were maintained on high-taurine; normal-taurine, normal-methionine; and low taurine, low-methionine diets. Urinary excretion and fractional excretion of taurine rose with the high-taurine diet and diminished with the low-taurine diet. Uptake of taurine was then studied using suspensions of isolated cortical tubule segments. When compared to normals, uptake was lower in the high-taurine group and greater in animals on the low-taurine diet. Evaluation of uptake kinetics shows an increase in maximum velocity (Vmax) with low-taurine diet, with no change in "apparent" Km. This suggests that the adaptation to dietary amino acid manipulation occurs through an alteration in the number of uptake sites, with no change in the affinity of the uptake system for the amino acid.
Original language | English (US) |
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Pages (from-to) | 2415-2419 |
Number of pages | 5 |
Journal | Life Sciences |
Volume | 29 |
Issue number | 23 |
DOIs | |
State | Published - Dec 7 1981 |
Bibliographical note
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