Pseudomonas elastase acts as a virulence factor in burned hosts by Hageman factor-dependent activation of the host kinin cascade.
Purified Pseudomonas elastase injected subcutaneously into the skin of an Evans blue dye-injected (intravenously) guinea pig caused dye leakage similar to that observed when histamine or bradykinin was injected in the same animal. The histamine-induced dye leakage was ablated in antihistamine-treated guinea pigs, but elastase- and bradykinin-induced dye leakages were not. Local injections of specific inhibitors of the host Hageman factor-dependent bradykinin-generating pathway given immediately prior to elastase injection reduced dye leakage in a dose-related manner. Elastase-related dye release was enhanced when angiotension-converting enzyme inhibitor, a substance which prevents host enzymes from breaking down bradykinin, was injected prior to elastase injection. We conclude that Pseudomonas elastase generates bradykinin in the infected host via a Hageman factor-dependent pathway.
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Department of Surgery, University of Cincinnati College of Medicine, Ohio 45219.
Neely
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D000818:Animals; D001920:Bradykinin / Q000378:metabolism*; D002056:Burns / Q000382:microbiology*; D002199:Capillary Permeability; D005174:Factor XII / Q000378:metabolism*; D006168:Guinea Pigs; D008297:Male; D010196:Pancreatic Elastase / Q000378:metabolism*; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000201:enzymology / Q000472:pathogenicity*
D005174:Factor XII; D007703:Peptidyl-Dipeptidase A; D010196:Pancreatic Elastase; D001920:Bradykinin