Fanapanel hydrate is a highly selective antagonist of AMPA/kainate with little activity against NMDA(Ki of 3.2 nM, 100 nM, and 8.5 μM against quisqualate, kainate, and NMDA, respectively).

In mice, ZK200775 elevated the threshold for AMPA- and kainate-induced clonic seizures with a THRD50 (threshold dose) of 2.9 (1.7–4.6) and 1.6 (1.3–2.0) mg/kg i.v., respectively, while the threshold for NMDA-induced seizures increased only at a THRD50 of 24.1 (21.9–26.5) mg/kg i.v., which affected motor coordination in the rotating rod with an ED50 of 14.6 (12.1–17.6) mg/kg. ZK200775 at doses of 10 and 30 mg/kg (intravenously) reduced muscle tone in hereditary spastic rats [1]. ZK200775 at 3.0 mg/kg, but not at 1.5 or 6.0 mg/kg, significantly reduced nicotine-induced (0.6 mg/kg) DA release in NACC and nicotine-stimulated LMA. ZK200775 (1.5, 3.0, 6.0 mg/kg) alone influenced neither DA release nor LMA. ZK200775 showed 34-fold selectivity for AMPA receptors compared to NMDA receptors and no affinity to nicotine receptors [2].