In vivo and in vitro effects of bromelain on PGE(2) and SP concentrations in the inflammatory exudate in rats.

The effects of bromelain were examined in rats with subcutaneous carrageenin-induced inflammation. After oral in vivo administration, bromelain (10 and 20 mg/kg p.o.) induced a significant decrease of both PGE(2) and substance P concentrations in the exudate. When added to the inflammatory exudate in vitro, the drug (25, 50, 100 microg/ml) did not affect PGE(2) concentrations and induced an increase in the substance P levels. Our data indicate that bromelain reduces the production of two key mediators of inflammation. This effect does not seem to be related to a direct action of the drug on PGE(2) and SP released in the exudate in response to the inflammatory stimulus.