L-803087 TFA is a highly potent and selective agonist of the somatostatin sst4 receptor, exhibiting a Ki value of 0.7 nM. It displays a remarkable selectivity, being over 280-fold more preferential for the sst4 receptor compared to other somatostatin receptors. Furthermore, L-803087 TFA promotes AMPA-mediated synaptic responses in hippocampal preparations and enhances kainate-induced seizures in mice.

SST5 receptor:3880 nM (Ki), SST2 receptor:4720 nM (Ki), SST3 receptor:1280 nM (Ki), SST1 receptor:199 nM (Ki), SST4 receptor:0.7 nM (Ki)

L-803087 exhibits affinity for cloned human sst1, sst2, sst3, and sst5 receptors with K_i values of 199, 4720, 1280, and 3880 nM, respectively[1]. It features a diamine moiety aligned with lysine on the pharmacophore; however, the connection between this molecule and the pharmacophore's aromatic and Trp (tryptophan) substituents remains unclear. Additionally, L-803087 does not suppress the secretion of growth hormone, insulin, or glucagon[1].

Administering 5 nmol of L-803087 on average doubles seizure activity in wild-type mice, an effect that is inhibited by 3 nmol of Octreotide. Additionally, in hippocampal slices from wild-type mice, 2 μM Octreotide does not alter AMPA-mediated synaptic responses, whereas 2 μM L-803087 induces facilitation[2].