Cyclooxygenase inhibitors attenuate augmented glutamate release in organum vasculosum laminae terminalis and fever induced by staphylococcal enterotoxin A.

Both the hyperthermia and augmented glutamate release in the organum vasculosum laminae terminalis (OVLT) after an intravenous dose (30 ng/kg) of staphylococcal enterotoxin A (SEA) were significantly reduced by pretreatment with intravenous administration of cyclooxygenase inhibitors such as aspirin (1 - 10 mg/kg), sodium salicylate (1 - 10 mg/kg), or diclofenac (10 mg/kg). Intra-OVLT administration of 50 - 200 microg in 1.0 microl of either aspirin or sodium salicylate 60 min before or 120 min after an intra-OVLT dose (50 microg in 1.0 microl) of glutamate also significantly suppressed the glutamate-induced hyperthermia. These findings suggest that inhibition of cyclooxygenase receptor mechanisms suppresses SEA fever by inhibition of glutamate release in the OVLT of rabbit brain.