The effects of bilobalide,a sesquiterpene isolated from Ginkgo biloba, on interelukin-1 (IL-l), tumor necrosis factor-α(TNF-α) and nitric oxide (NO) production in resting and lipopolysaccharide (LPS )-stimulated cultured neonatal rat microglia were studied. Apafant, a platelet activating factor (PAF) antagonist of triazolobenzodiazepine type was ttsed as control.The biological activities of IL-1 and TNFαwere tested