ACPT-I is an agonist of the group III metabotropic glutamate receptors (mGluRs) mGluR4a and mGluR8 (EC50s = 7.2 and 8.2 μM, respectively) that has no effect on mGluR1a or mGluR2. It has diverse biological activity, including neuroprotective, anticonvulsant, and anxiolytic-like effects. ACPT-I (1-200 μM) reduces cell death following oxygen-glucose deprivation in primary neuronal cultures and in a rat model of middle cerebral artery occlusion when used at a dose of 30 mg/kg. It is neuroprotective against excitotoxicity induced by kainite in vitro and in vivo and reduces the incidence of clonic seizures in various seizure models in mice and rats (ED50s = 0.08-49.3 nM, i.c.v.). ACPT-I also has anxiolytic-like effects in mice and rats, however, these effects can be blocked by WAY-100635 and flumazenil , indicating the involvement of the serotonin (5-HT) receptor subtype 5-HT1A and GABAA receptor.
