Interleukin-1(IL-1)and opioid peptides,acting as neuromodulators,play roles in excitotoxicity of neurons.The interaction of IL-1,opioid peptides and imrnediate early genes c-fos and c-jun in rat corticocerebral cells was studied.The results showed that IL-1 βinduced transient and early c-fos and c-jun mRNA expression.The induction of c-fos and c-jun mRNA by IL-1 appeared within 15 min,was highest respectively. Addition to corticocerebal cells of antisense oligonucleotides to c-fos and c-jun, significantly in hibit the secretion of Leu-enkephalin and β-endorphin of antisense oligonucleotides to c-fos and c-jun appeared the dose response curve. These findings suggest that immediate early signals Fos and Jun partly regulate secretion of enkephalin and β-endorphin of corticocere bral cells induced by IL-1.