Evidence for the activation of the kallikrein-kinin system in experimental asbestosis

Immunoreactive bradykinin (BK) and its metabolites, namely des-Arg9-BK and des (Phe8,Arg9)-BK, were measured in acidic extracts of lungs from normal and asbestos-treated guinea pigs. The development of experimental asbestosis did not change the levels of BK (0.67 ng/mg and 0.72 ng/mg) while the levels of des-Arg9-BK increased from 0.06 to 0.57 ng/mg (P less than 0.01) and those of des (Phe8,Arg9)-BK, from 0.09 to 1.48 ng/mg (P less than 0.01). These increases in the amount of the BK metabolites suggest the participation of the kallikrein-kinin system in the inflammatory reaction induced by the intratracheal administration of asbestos into guinea pigs.