AJP - Renal Physiology, Vol 251, Issue 1 125-F131, Copyright © 1986 by American Physiological Society
Effect of amino acid intake on brush-border membrane uptake of sulfur amino acids
R. W. Chesney, N. Gusowski, M. Padilla and S. Lippincott
Alterations in the intake of sulfur amino acids (SAA) changes the rat renal
brush-border membrane uptake of the beta-amino acid, taurine. A low-SAA
diet enhances and a high-taurine diet reduces uptake (Chesney et al.,
Kidney Int. 24: 588-594, 1983). Neither the low-SAA diet nor the
high-taurine diet alters the time course or concentration-dependent
accumulation of the sulfur amino acids methionine and cystine or of
inorganic sulfate. By contrast the uptake of beta-alanine, another
beta-amino acid that competes with taurine, is greater in animals on the
low-SAA diet. The high-taurine diet does not change beta-alanine uptake.
The plasma levels of taurine are altered by dietary change, but not the
values for methionine and cystine. This study indicates that renal
adaptation is expressed for beta-alanine, a nonsulfur-containing beta-amino
acid. By contrast, methionine, cystine, and sulfate, which participate in a
variety of synthetic and conjugative processes, are not conserved by the
renal brush-border surface following ingestion of either a low-methionine
and -cystine diet or high-taurine diet.
