Histamine induction and release following proteolytic enzyme exposure.

The mechanism of biologic response from exposure to a 12% subtilisin Carlsberg preparation is shown to be one of histamine release in the guinea pig. Three groups of guinea pigs were pretreated by intradermal injections withsaline solution of (1) the commercial proteolytic enzyme preparation containing 12% subtilisin Carlsberg, (2) an alkaline protease preparation obtain from Aspergillus oryzae that was isolated from cotton dust, or (3) a nonproteolytic mixture of proteins and lipases obtained from cotton seeds. The histamine content of the ling, liver, and ear tissues of guinea pigs that were pretreated with any one of the three preparations showed an in untreated animals. Following challenge by intratracheal injection of a saline solution containing the subtilisin preparation, the guinea pigs pretreated with the same preparation showed a markedly reduced liver histamine level. Challenge by inhalation exposure to the subtilisin preparation of guinea pigs that were pretreated with any one of the above preparations resulted in a lower histamine concentration in the lungs and livers.