February 2007 Discusses the work of NIDA’s Division of Basic Neuroscience and Behavioral Research, the Institute’s locus for studies into the fundamental brain mechanisms underlying drug abuse and addiction.
New research suggests that differences in tobacco consumption reflect, in part, differences in the functional efficacy of a specific type of receptor in a pathway of the brain. In animal studies, nicotinic acetylcholine receptors with the α5 subunit played a key role in producing aversive responses to nicotine, thereby dissuading further consumption of the drug.
Microneedles are an innovative technique for delivering medications through the skin, a route that could particularly benefit patients receiving naltrexone therapy for opioid and alcohol dependence. Researchers have found a way to use the transdermal technique to deliver a single treatment of naltrexone that lasts for 7 days.
Soluble-film preparations of buprenorphine suppressed heroin abusers’ withdrawal symptoms with no serious side effects in a recent clinical trial. They dissolved more rapidly in the mouth than the pill form of the medication, providing faster relief.
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.
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.