lypressin

noun

ly·​pres·​sin ˌlī-ˈpres-ᵊn 

: a vasopressin in which the eighth amino acid residue in its polypeptide chain is a lysine residue (as in pigs) rather than an arginine residue (as in most mammals including humans) and which is used especially as a nasal spray in the control of diabetes mellitus

called also lysine vasopressin

compare arginine vasopressin