Orphan receptor. Probably involved in the function of nociceptive neurons. May regulate nociceptorfunction and/or development, including the sensation or modulation of pain. Cortistatin-14 seems to be a highpotency ligand at this receptor. Cortistatin has several biological functions including roles in sleep regulationlocomotor activity, and cortical function. In receptor-expressing cells, cortistatin-stimulated increases inintracellular Ca(2+) but had no effect on basal or forskolin-stimulated cAMP levels, suggesting that thisreceptor is G(q)-coupled.