Correspondence to:

Corticotrophin-releasing factor (CRF) belongs to a family of related neuropeptides that regulate a variety of physiological processes associated with the maintenance of homeostasis during stress (1). In fish, other members of the CRF family include urotensin-I (UI; orthologue to tetrapod urocortin, UCN), and homologous peptides to mammalian UCN-2 and-3 (2). CRF is perhaps best known as the apex hormone of the hypothalamic-pituitary-inter-renal (HPI) axis that controls circulating levels of glucocorticoids; however, CRF-related peptides play a diverse role in mediating an animal’s response to stress (3), including cardiovascular modulation (4) and altered food intake (5). CRF-related peptides signal through a com-mon family of receptors (6,7) and are further modulated by a shared binding protein (CRF-BP) (8). CRF-BP is a highly conserved 37-kDa protein originally isolated from human plasma (9) and is present in all vertebrate classes (8). With a high-affinity for all CRF-related peptides (10) and a broa