PURPOSE: To provide a peptide having various physiological activities such as the release of an ileal contraction action and the contraction action of canine mesenteric arteria with prostaglandin F2α, an angiotensin transferase-inhibiting action, and a vasodepressor activity.

CONSTITUTION: The peptide of formula: H-(A)-Tyr-(B)-Val-(C)-(D)-Leu-Leu-Arg- OH [(A) is Arg-His-Pro-Glu, His-Pro-Glu, Arg-His-Pro-Asp, His-Pro-Asp, or single bond; (B) is Ala or Ser; (C) is Val or Ser; (D) is Val or Leu] or its salt, which are used as medicines.