UBP-282

UBP-282 is a potent, selective and competitive AMPA and kainate receptor antagonist. UBP-282 inhibits the fast component of the dorsal root-evoked ventral root potential (fDR-VRP) with an IC₅₀ value of 10.3 μM. UBP-282 antagonizes kainate-induced depolarisations of dorsal roots with a pA₂ value of 4.96^[1][2]. IC50 & Target: IC50: 10.3 μM (fast component of the dorsal root-evoked ventral root potential (fDR-VRP))^[1]
pA2: 4.96 (Kainate<-induced depolarisations of dorsal roots)^[1] In Vitro: UBP-282 (3-CBW) is selective for AMPA- and GluR5-containing kainate receptors vs NMDA, mGlu and kainate receptors expressed on motor neurones^[1][2].
UBP-282 (3-CBW), at a concentration of 200 μM, blocks AMPA evoked depolarizations on motoneurones while responses to equi-effective doses of NMDA and DHPG were relatively unaffected. In the presence of 200 μM UBP-282, a concentration that completely abolishes AMPA-evoked depolarizations on motoneurones and kainate-evoked responses on dorsal root, there is still a noticeable depolarization evoked by kainate on motoneurones^[1]. In Vivo: On neonatal rat motoneurones UBP-282 (3-CBW) (200 μM) almost completely abolished responses to AMPA while responses to NMDA, kainate and DHPG were 101.6%, 39.4% and 110.5% of control, respectively. UBP-282 can therefore be used to isolate kainate receptor responses from those mediated by AMPA receptors^[1].