Involvement of nuclear factor-kB in the expression of opiate withdrawal.

1. To investigate the role of NF-kB in the expression of opiate withdrawal, the effects of PDTC, an inhibitor of NF-kB activation, was studied on acute opiate withdrawal induced by morphine in vitro. 2. After a 4 min in vitro exposure to morphine, a strong contracture of guinea pig isolated ileum was observed after the addition of naloxone. 3. PDTC (1x10(-8)-5x10(-8)-1x10(-7) M) was able to reduce the naloxone-induced contracture after exposure to the opioid agonist in a concentration-dependent fashion. 4. The results of the present study indicate that NF-kB is involved in the expression of opiate withdrawal thus extending and explaining previous papers performed with dexamethasone and selective arachidonic acid metabolites inhibitors.