The Profile of Vascular Permeability Factors in Dilute Guinea-pig Plasma

摘要

Kininogenase, kinins and factors that increase vascular permeability were generated during the incubation of dilutions of guinea-pig plasma activated by exposure to glass. Permeability-increasing activity persisted after the disappearance of the kininogenase and kinins.Kininogenase-free preparations of the major permeability factor contained an activator of the same prekininogenase of plasma that is involved in the glass activated system. Evidence for the identity of the permeability factor with the activator was given by their equal susceptibility to heating and to inhibition by an esterase inhibitor, and also by the close correspondence of permeability-increasing and activator potencies in a number of serum fractions.Since the major permeability factor, PF dil, did not release kinins from heated substrates, it was distinguishable from kininogenase II, an enzyme described for the plasma of some mammalian species which is both an activator and a kininogenase.The sequence HF—PF dil—kininogenase was confirmed as a possible pathway to kinin release in dilute plasma of the guinea-pig. However, the results do not lend support to the interpretation that kininogenase II and PF dil are identical in this species.