Immunogen sequence: APHEDARLTP EELERASLLQ ILPEMLGAER GDILRKADSS TNIFNPRGNL RKFQDFSGQD PNILLSHLLA RIWKPYKKRE TPDCFWKYCV. Urotensin II is an active cyclic heptapeptide absolutely conserved from lamprey to human. The active peptide acts as a vasoconstrictor