Gamma-aminobutyric acid uptake by rat kidney brush-border membrane vesicles

Summary Brush-border membrane vesicles (BBMV) from rat kidney cortex possessed two uptake systems for -aminobutyric acid (GABA), a high affinity system (Km=10.9 M) and a low affinity system (Km=1203 M). Both uptake systems were inhibited by p-hydroxymercuribenzoic acid and ouabain, and by the action of neuraminidase, whereas the GABA analogs nipecotic acid, -alanine, 2,4-diaminobutyric acid and 4,5,6,7-tetrahydroisoxazolo-4,5c]-pyridin-3-ol had no effect on the GABA uptake activity. The BBMW uptake systems were clearly different from the GABA transport systems present in brain tissue.