부산대학교 도서관

(2S,1ʼS,2ʼR)-2-(Carboxycyclopropyl)glycine (L-CCG III) was a substrate of Na-dependent glutamate transporters (GluT) in Xenopus laevis oocytes (IC50 ∼ 13 and ∼2 μM for, respectively, EAAT 1 and EAAT 2) and caused an apparent inhibition of [H]L-glutamate uptake in “mini-slices“ of guinea pig cerebral cortex (IC50 ∼ 12 μM). In slices (350 μM) of guinea pig cerebral cortex, 5 μM L-CCG III increased both the flux of label through pyruvate carboxylase and the fractional enrichment of glutamate, GABA, glutamine and lactate, but had no effect on total metabolite pool sizes. At 50 μM L-CCG III decreased incorporation of C from [3-C]-pyruvate into glutamate C4, glutamine C4, lactate C3 and alanine C3. The total metabolite pool sizes were also decreased with no change in the fractional enrichment. Furthermore, L-CCG III was accumulated in the tissue, probably via GluT. At lower concentration, L-CCG III would compete with L-glutamate for GluT and the changes probably reflect a compensation for the “missing“ L-glutamate. At 50 μM, intracellular L-CCG III could reach > 10 mM and metabolism might be affected directly.