H-Ala-Lys-Phe-Asp-Lys-Phe-Tyr-Gly-Leu-Met-NH2

Scyliorhinin I is a tachykinin-1 (NK-1) and tachykinin-2 (NK-2) receptor agonist with a Ki value of 0.9 nM for rat submandibular gland NK-1 receptor and 2 nM for hamster bladder NK-2 receptor. Scyliorhinin I has the ability to contract the longitudinal muscles of the guinea pig ileum[1][2].

rat NK1: 0.9 nM (Ki); guinea pig NK-2: 2 nM (Ki)

[1] Conlon, et al. "Scyliorhinin I and II: two novel tachykinins from dogfish gut." FEBS letters 200.1 (1986): 111-116. DOI:10.1016/0014-5793(86)80521-x
[2] Stephen H, et al. "The dogfish peptides scyliorhinin I and scyliorhinin II bind with differential selectivity to mammalian tachykinin receptors." European journal of pharmacology 144.1 (1987): 109-111. DOI:10.1016/0014-2999(87)90017-3