Ibotenic acid has agonist activity at both the N-methyl-D-aspartate (NMDA) and trans-ACPD or metabolotropic quisqualate (Q_m) receptor sites. IC50 & Target: NMDA receptor^[1] In Vitro: Ibotenic acid (Ibo) is capable of acting at both NMDA and trans-ACPD receptors in the CNS, although only activation of NMDA receptors is involved in Ibo neurotoxicity. Ibotenic acid is toxic to cortical neurons exposes for 5 min with an EC₅₀=77.3±8 μM (n=5) as measured by release of lactate dehydrogenase to the culture media^[1].