DL-threo-β-Hydroxyaspartic acid is an inhibitor of excitatory amino acid transporters (EAATs).^1,2It inhibits glutamate uptake in COS-1 cells expressing human EAAT1 or EAAT2 (IC₅₀s = 96 and 31 µM, respectively) as well as inward currents induced by L-aspartate in EAAT4-expressingXenopusoocytes (K_i= 0.6 µM) and by L-glutamate in EAAT5-expressing oocytes (K_i= 2.5 µM) voltage-clamped at -60 mV. Intrathecal administration of DL-threo-β-hydroxyaspartic acid (7.5 and 15 µg/animal) reduces the number of flinches and shakes in the second phase of the formalin test in rats.³

1.Shimamoto, K., Lebrun, B., Yasuda-Kamatani, Y., et al.??-threo-β-benzyloxyaspartate, a potent blocker of excitatory amino acid transporters.Mol. Pharmacol.53(2)195-201(1998) 2.Shigeri, Y., Shimamoto, K., Yasuda-Kamatani, Y., et al.Effects of threo-β-hydroxyaspartate derivatives on excitatory amino acid transporters (EAAT4 and EAAT5)J. Neurochem.79(2)297-302(2001) 3.Yaster, M., Guan, X., Petralia, R.S., et al.Effect of inhibition of spinal cord glutamate transporters on inflammatory pain induced by formalin and complete Freund’s adjuvantAnesthesiology114(2)412-423(2011)