Peripheral Vasodilator Action of Eledoisin, Bradykinin, and Nitroglycerin in Anesthetized Dogs

The peripheral vasodilator action of the endecapeptide eledoisin in the anesthetized dog has been described in this paper. Blood flow through the vascular beds supplied by the femoral artery increased following doses of eledoisin as low as 0.5 nanogram/kg (4.25·10 -13 mole/kg) injected intravenously, and 0.001 ng/kg (8.5·10 -16 mole/kg) injected intra-arterially. The blood vessels of the skin were less reactive than blood vessels in muscle. Eledoisin exerted a powerful vasodilator effect on vascular beds supplied by the common carotid, the external and internal carotid, the occipital and the vertebral arteries. Renal and mesenteric vascular beds did not respond significantly to eledoisin. Comparison with some other vasodilator drugs was made. Following intra-arterial doses which do not affect systemic blood pressure, eledoisin was 5 to 50 times more active than bradykinin on total femoral and muscle flows; both showed the same activity on skin flow. Nitroglycerin, carbaminoylcholine, and papaverine were even less active than bradykinin.