Effect of synthetic bradykinin on contractile tension of human saphenous vein strips

The ability of synthetic bradykinin to contract isolated helically-cut human saphenous vein strips was studied in vitro. Bradykinin (0.05-2.0 mcg/ml) consistently failed to contract human vein strips. Similarly prepared rabbit aortic strips also failed to contract when exposed to bradykinin in the concentration range studied. Bradykinin-insensitive vein and aortic strips responded with substantial increases in contractile tension when exposes to (PGE2) prostaglandin E2 noradrenaline histamine and KC1. However bradykinin (0.1 mcg/ml) was capable of relaxing human vein strips which had contracted in response to PGE2. (Authors modified)