Cortistatin 14 is a neuropeptide expressed in inhibitory neurons of the cerebral cortex. Depresses neuronal activity, and induces slow-wave sleep, likely through antagonism of acetylcholine. It is structurally and functionally similar to somatostatin 14. Competes with somatostatin 14 for binding of somatostatin receptors (IC50s=5, 0.09, 0.3, 0.2, and 0.3nM for receptors sst1-5, respectively).