From the article:

Cocaine relapse was significantly reduced in a preclinical model when brain-derived neurotropic factor (BDNF) was applied to the nucleus accumbens deep in the brain immediately before cocaine-seeking behavior, report investigators at the Medical University of South Carolina (MUSC) in an article published online in June 2018 by Addiction Biology.

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While other research groups have studied how BDNF administration affects drug self-administration and relapse, no one has looked at what happens if BDNF is given immediately before relapse.

Since low serum BDNF levels are seen in cocaine-dependent patients compared to non-addicts, the MUSC researchers sought to better understand the connection between BDNF and cocaine relapse. The nucleus accumbens was selected as the focal point for BDNF administration since it is a central component of the brain reward circuit.

“An important aspect of this study is that while others have shown that BDNF is important for establishing the state of addiction, we find that can also be used to reverse addiction,” says Peter Kalivas, Ph.D., professor and chair in the Department of Neuroscience. “This exemplifies that the primary effect of BDNF is to promote changes in the brain, and that this capacity to change the brain contributes to how people get addicted, but also can be harnessed to remove brain pathologies such as drug addiction.”

The findings reported in Addiction Biology are the first to show that applying BDNF to the nucleus accumbens immediately before the reinstatement phase, when the rats are once again seeking cocaine due to cue exposure, greatly reduces relapse.