Amino Acid Transport In Cultures Research Articles

Effects of membrane stabilizers on glucuronidation and amino acid transport in cultures of rat hepatoma cells.

Abstract: Promazine and imipramine in concentrations between 0.005 mM and 0.20 mM, and thioridazine between 0.005 mM and 0.10 mM inhibit p‐amino‐phenol glucuronidation in rat hepatoma cell cultures. The cardiac stabilizers propranolol and quinidine have little or no effect on glucuronidation. In a homogenate system prepared from the cells promazine, thioridazine, and imipramine between 0.1 and 1.0 mM also inhibit p‐arninophenol glucuronidation. In addition, promazine, thioridazine, and imipramine inhibit alanine uptake/incorporation, α‐aminoisobutyric acid uptake and efflux in the cultures of hepatoma cells.

Tryptophane transport in cultures of human fibroblasts.

SummaryA method is described which permits kinetic studies of amino acid transport in cultures of human fibroblasts. Approximately linear kinetics of uptake were found to obtain during the first 8 minutes of incubation in medium containing puromycin and L-tryptophane H3, in the absence of other amino acids (“non-competitive medium”). Specific activities of monolayers pulsed in such media were more than 10 times those which were obtained in the presence of competing amino acids. The rate of uptake (in non-competitive medium) for one strain was almost double the mean rate obtained for 4 other presumably normal diploid strains, suggesting that the method might be useful as a marker for in vitro somatic cell genetic studies. The potential usefulness of the method for investigations of cystinuria and Hartnup Disease are discussed.