title: Regulatory characteristics of amino acid transport in newborn rat renal cortex cells.
abstract: The uptaken of alpha-aminoisobutyric acid by slices of kidney cortex from newborn rats is enhanced by a preliminary incubation of the tissue in buffer at 37 degrees C. This effect is abolished by anaerobiosis, the presence of dinitrophenol or the removal of Na+ during the preliminary incubation. Cycloheximide (50 muM) and purimycin (1 mM) as well as alpha-aminoisobutyric acid, glycine and proline (5 mM) in the preincubation buffer also abolish the effect, while actinomycin D (0.8 muM) partially the phenomenon indicates that the enhanced uptake is due to an increased entry rate into the cells without a change in effux. There is no alteration in the apparent transport Km but an increase in the V for entry. The effect is dependent on tissue age being observed between birth and 22 days, after which there is a decrease in response to preliminary incubation with no effect seen in adult tissues.
mesh_terms: D000375:Aging; D000596:Amino Acids / Q000378:metabolism*; D000621:Aminoisobutyric Acids / Q000378:metabolism; D000693:Anaerobiosis; D000818:Animals; D000831:Animals, Newborn; D001693:Biological Transport, Active; D003513:Cycloheximide / Q000494:pharmacology; D003515:Cycloleucine / Q000378:metabolism; D003609:Dactinomycin / Q000494:pharmacology; D004140:Dinitrophenols / Q000494:pharmacology; D005998:Glycine / Q000378:metabolism; D066298:In Vitro Techniques; D007672:Kidney Cortex / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D007700:Kinetics; D010042:Ouabain / Q000494:pharmacology; D011392:Proline / Q000378:metabolism; D011691:Puromycin / Q000494:pharmacology; D051381:Rats; D012964:Sodium / Q000494:pharmacology
chemical_list: D000596:Amino Acids; D000621:Aminoisobutyric Acids; D004140:Dinitrophenols; D003515:Cycloleucine; D003609:Dactinomycin; D011691:Puromycin; D010042:Ouabain; D003513:Cycloheximide; D011392:Proline; D012964:Sodium; D005998:Glycine