Urocortin II (mouse) exhibited considerably higher affinity for both splice variants of the type 2 CRF receptor (CRF-R2) than for CRF-R1. The potencies of Ucn II (mouse) in activating CRF-R2α and CRF-R2β were nearly equivalent to that of urocortin (rat). Hsu, S.Y.; et al., Nat. Med., 7, 605 (2001); Lewis, K.; et al., Proc. Natl. Acad. Sci. USA, 98, 7570 (2001); Reyes, T.M.; et al., Proc. Natl. Acad. Sci. USA, 98, 2843 (2001).