Activity of the enantiomers of erythro-3-hydroxyaspartate at glutamate transporters and NMDA receptors

作者:Foster Alan C; Li Yong Xin*; Runyan Stephen; Dinh Tim; Venadas Steven; Chen June; Pashikanti Srinath; Datta Apurba; Ehring George; Staubli Ursula
来源:Journal of Neurochemistry, 2016, 136(4): 692-697.
DOI:10.1111/jnc.13430

摘要

The enantiomers of erythro-3-hydroxyaspartate were tested for activity at glutamate transporters and NMDA receptors. Both enantiomers inhibited glutamate transporters in rat hippocampal crude synaptosomes and elicited substrate-like activity at excitatory amino acid transporter 1, 2, and 3 as measured by voltage clamp in the Xenopus oocyte expression system. The enantiomers had similar affinities, but the D-enantiomer showed a lower maximal effect at excitatory amino acid transporter 1, 2, and 3 than the L-enantiomer. Surprisingly, D-erythro-3-hydroxyaspartate was a potent NMDA receptor agonist with an EC50 value in rat hippocampal neurons of 320nM, whereas the L-enantiomer was 100-fold less potent. L-erythro-3-hydroxyaspartate showed activity at both glutamate transporters and NMDA receptors at concentrations that are reported to inhibit serine racemase, indicating a lack of selectivity. This enantiomeric pair may assist in shedding further light on the structural requirements for substrate activity at glutamate transporters and for agonist activity at NMDA receptors.

  • 出版日期2016-2

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