Abstract
Brush-border membrane vesicles (BBMV) from rat kidney cortex possessed two uptake systems for γ-aminobutyric acid (GABA), a high affinity system (Km=10.9 μM) and a low affinity system (Km=1203 μM). Both uptake systems were inhibited by p-hydroxymercuribenzoic acid and ouabain, and by the action of neuraminidase, whereas the GABA analogs nipecotic acid, β-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.