Transport of amino acids into the oestrogen-primed uterus. Enhancement of the uptake by a preliminary incubation

摘要: 1. Preincubation of the immature rat uterus under physiological conditions was found to increase its subsequent ability transport alpha-aminoisobutyric acid, l-proline, l-alanine and 1-aminocyclopentanecarboxylic acid. Uptakes l-valine, l-phenylalanine l-leucine were not affected. With a doubling uptake could be obtained after 3-5h preincubation period. Uteri from oestradiol-primed rats gave increases similar those in tissues untreated animals. In both cases increased V(max.) acid but did affect K(m). 2. The during period determined No if carried out at 1 degrees C, presence cyanide or dinitrophenol, anaerobiosis with concentration puromycin that depressed incorporation into protein by 95%. also shown prevent normally addition, no Na(+) omitted medium. Other inorganic ions had smaller effects. 3. uteri before showed same general patterns sensitivity competitive inhibitors, K(+), pH, temperature 2,4-dinitrophenol. 4. results suggest leads an component ;A system' for amino uterus, metabolic energy is required reactions involved.