A brain response occurs in the nucleus accumbens when rats encounter a cue that they associate with previous cocaine self-administration, but not a cue associated with a pleasurable non-drug experience. Moreover, the response correlates in time and intensity with the animals’ cue-induced relapse to cocaine-seeking.
More than half of heroin-addicted patients treated with naltrexone via an implanted delivery device maintained abstinence throughout a 6-month clinical trial in Saint Petersburg, Russia. The implant device, which releases a steady dose of naltrexone continuously for 2 months, averted relapse to heroin use three times as effectively as daily oral doses of the medication.
Clinical trials of N-acetylcysteine to help people recovering from drug abuse avoid relapse have demonstrated only moderate efficacy. New NIDA-supported research shows that while a low dose of the medication activates receptors associated with lowered drug-seeking behavior, a higher dose appears to activate receptors associated with increased drug-seeking behavior. The result suggests that a medication or combination of medications that stimulate the receptor GluR2/3 and block mGluR5 may work better than N-acetylcysteine alone.
November 2011 In a new series of studies tracing the molecular events that occur in the brain as memories are formed and preserved, researchers find that certain epigenetic changes may promote vulnerability to relapse.