The effects of cyclooxygenase inhibition on chemiluminescence and aggregation in sheep neutrophils

Antiinflammatory actions of cyclooxygenase inhibitors may be related to inhibition of the synthesis and release of prostaglandins and thromboxane or to nonspecific actions of particular drugs. The role of cyclooxygenase products of arachidonic acid was studied in two leukocyte functions, free radical release and aggregation, after complement activation. Dose response curves were constructed after treatment with meclofenamate or ibuprofen. To differentiate between effects on free radical release from complement activated neutrophils and scavenging free radicals, additional experiments were made with a cell free system to generate free radicals. Both drugs inhibited complement initiated neutrophil chemiluminescence in a dose dependent manner. Meclofenamate acted primarily as a scavenger while ibuprofen inhibited free radical release. Neither drug had any inhibitory effects on complement induced leukocyte aggregation.