Autoreversal of bradykinin response in the perfused isolated canine hind limb

The vascular effects of synthetic bradykinin were studied in perfused isolated canine hind limb preparations. Repeated low doses of bradykinin or high doses administered at sufficiently long time intervals elicited dose-related hypotensive responses. In contrast, administration of bradykinin at short time intervals led first to diminishing hypotensive responses followed by frank increases in perfusion pressure. This autoreversal of bradykinin response tentatively was explained on the basis of known effects of bradykinin on prostaglandin synthesis with specific reference to PGF2 alpha.