(S)-Willardiine is a potent agonist of AMPA/kainate receptors with EC50 of 44.8 uM. IC50 value: 44.8 uM(EC50) [1] Target: AMPA/kainate receptor agonist in vitro: The (S)- but not (R)-isomers of willardiine and 5-bromowillardiine were potent agonists, producing rapidly but incompletely desensitizing responses [1]. At a concentration of 1.8 mM, Ca2+ inhibited the currents induced by 100 microM willardiine by approximately 50% [2]. in vivo: In newborn mice (P5, histopathology at P10), local injection of the AMPA receptor agonist S-bromo-willardiine at day 5 after birth induced cortical damage and white matter damage, which was reduced in a dose-dependent manner by the AMPA receptor antagonists [3].