Cortistatin 14 is an endogenous neuropeptide, mainly expressed in the cortex and hippocampus, that has structural and functional similarities to somatostatin-14. Cortistatin 14 displays potency at all somatostatin receptors (sst1 - sst5) and prevents somatostatin-14 binding (IC50 values are 0.09, 0.2, 0.3, 0.3 and 5 nM at sst2, sst4, sst3, sst5 and sst1 receptors, respectively). Also a potent MRGPRX2 agonist (EC50 = 25 nM in HEK293 cells) and binds to the growth hormone secretagog receptor (GHS-R1a). Exhibits neuronal depressant and sleep-modulating properties in vivo.