kynurenic acid

Kynurenic acid (Quinurenic acid) is an endogenous tryptophan active metabolite, a triple antagonist of NMDA, glutamate, α7 nicotinic acetylcholine receptor, and an agonist of GPR35 CXCR8 with neuroprotective and anticonvulsant properties. It has neuroprotective and anticonvulsant properties and can be used to study neurodegeneration and metabolism-related diseases.

7-Chlorokynurenic acid (7-chloro-4-hydroxy-2-carboxyquinoline) is an effecitve and selective antagonist of NMDA receptor with IC50 of 0.56 μM for the glycine B coagonist site. 7-Chlorokynurenic acid inhibits the reuptake of glutamate into synaptic vesicles with a Ki of 0.59 μM and shows antinociceptive actions after neuraxial delivery.

6-Hydroxykynurenic acid (6-HKA), a kynurenic acid (KYNA) derivative isolated from Ginkgo leaves, functions as a low-affinity NMDAR antagonist with an IC50 of 59 μM [1].

Aminoadipic acid (DL-2-Aminoadipic acid) (2-aminoadipate) is a metabolite in the principal biochemical pathway of lysine. It is an intermediate in the metabolism (i.e. breakdown or degradation) of lysine and saccharopine. It antagonizes neuroexcitatory activity modulated by the glutamate receptor N-methyl-D-aspartate (NMDA). Aminoadipic acid has also been shown to inhibit the production of kynurenic acid, a broad spectrum excitatory amino acid receptor antagonist, in brain tissue slices.