Disorders of Amino-Acid Transport

Effect of acidic (dicarboxylic) alpha‐amino acids on uptake of L‐histidine by intestinal mucosa, testis, spleen and kidney in vitro: a comparison with effect in brain.

“…In general, there appear to be several transport systems for amino acids (Milne, 1964), which can overlap to some extent (Neame, 1964;Newey & Smyth, 1964 (Webber et al 1961;Webber, 1962), with possible further subdivision of the latter (Beyer et al 1947). A similar situation probably exists in small intestine (Wiseman, 1955;Lin, Hagihira & Wilson, 1962;Newey & Smyth, 1964).…”

Renal tubular transport of proline, hydroxyproline, and glycine

“…was evident that cellular uptake of these solutes by many different tissues is mediated wholly, or in part, by a transport agency with preference for them (1)(2)(3)(4)(20)(21)(22)(23). Several investigators have now observed sibships or families (18,19,24,25 and footnotes 2 and 3) in which iminoglycinuria persisted beyond the period of infancy when this is a normal phenomenon (23).…”

Cellular transport of l-histidine in Hartnup disease

“…Thus in the patient 17% and in control C, 0.3% of the intravenously given dose was passed unchanged into the urine. DISCUSSION Milne (17) has set forth criteria for malabsorption of amino acids. He states that after ingestion of an amino acid there should be, when compared with controls, a lesser augmentation in the plasma concentration of the amino acid, more of the amino acid should appear in the feces, and finally, unusual bacterial strains may appear in the stools owing to an abnormal environment.…”