SJM-3 is a positive allosteric modulator of different isoforms of the GABAA receptor. SJM-3 binds at the high-affinity benzodiazepine binding site at the α+/γ- subunit interface[1].
SJM-3 binds at the high-affinity benzodiazepine binding site at theα+/γ- subunit interface but effects its action through another site presumably located within the transmembrane domain. The binding affinity of SJM-3 at wild type receptors is determined by displacement of [3H]-Flunitrazepam and [3H]-Ro15-1788 and indicates a Ki of SJM-3 amounting to 218±70 nM and 242±38 nM, respectively[1].
[1]. Simon J Middendorp, et al. Positive modulation of synaptic and extrasynaptic GABAA receptors by an antagonist of the high affinity benzodiazepine binding site. Neuropharmacology. 2015 Aug;95:459-67.