Leukotriene B4 production and pharmacologic regulation of reverse passive Arthus pleurisy: importance of antigen dose.

Immunoreactive leukotriene B4 (iLTB4), detected in the pleural cavity following induction of a reverse passive Arthus reaction (RPAR), was inhibited by the mixed lipoxygenase-cyclooxygenase inhibitors, phenidone and BW 755C, but not by cyclooxygenase inhibitors or by chlorpheniramine or methysergide. Both iLTB4 production and the subsequent pleural inflammation were dependent upon the dose of BSA antigen employed to elicit the RPAR pleurisy. However, inasmuch as BW 755C and phenidone were not distinguished from the cyclooxygenase inhibitors in their effects on fluid accumulation and cellular infiltration in RPAR pleurisy, it is doubtful that LTB4 plays a functional role in this inflammation model.