L-803087

L-803087 is a potent and selective somatostatin sst4 receptor agonist with a K_i of 0.7 nM. L-803087 is >280-fold higher than other somatostatin receptors. L-803087 facilitates AMPA-mediated hippocampal synaptic responses in vitro and increases kainate-induced seizures in mice^[1][2]. IC50 & Target: Ki: 0.7 nM (sst4 receptor), 199 nM (sst1 receptor), 4720 nM (sst2 receptor), 1280 nM (sst3 receptor) and 3880 nM (sst5 receptor)^[1] In Vitro: L-803087 has K_i values for cloned human sst1, sst2, sst3 and sst5 receptors of 199, 4720, 1280 and 3880 nM, respectively^[1].
L-803087 has a diamine moiety that maps to lysine on the phmacophore, but relation of this molecule to the aromatic and the Trp substituents of the phmacophore are not obvious. L-803087 does not inhibit secretion of growth hormone, insulin, or glucagon^[1]. In Vivo: L-803087 (5 nmol) is doubled seizure activity in wild-type mice on average. Interestingly, this effect is blocked by 3 nmol Octreotide. In hippocampal slices from wild-type mice, Octreotide (2 μM) does not modify AMPA-mediated synaptic responses while facilitation occurred with L-803087 (2 μM)^[2].