White Lines
Something like a phenomenon – US scientists are unraveling the neuroscience behind cocaine addiction
Researchers at The Scripps Research Institute (TSRI) have found new evidence that a TrkB receptor inhibitor can reverse cocaine dependency in rodents (1). TrkB blockade led to mixed results in previous studies, depending on which region of the brain was targeted, but TSRI’s study shows that system-wide delivery causes cocaine-addicted rats to self-administer less of the drug and made them less likely to re-start cocaine use after a period of abstinence.
Cocaine re-wires the brain, making addicts desperate for a fix even after the immediate physical withdrawal has passed. University of Buffalo scientists have discovered an important component of the complex physiological pathways that induce cocaine cravings after withdrawal (2). The researchers found that expression of BRG1 protein is upregulated in cocaine-addicted rats after seven days’ abstinence. BRG1 was also seen to interact with transcription factors previously implicated in mediating gene expression after cocaine use.
Both groups hope that their findings can one day be translated into new treatments to help recovering addicts stay clean.
- MM Verheij et al., “Systemic delivery of a brain-penetrant TrkB antagonist reduces cocaine self-administration and normalizes TrkB signaling in the nucleus accumbens and prefrontal cortex”, J Neurosci 36, 8149–8159 (2016).
- Z-J Wang et al., “BRG1 in the nucleus accumbens regulates cocaine-seeking behavior”, Biol Psychiatry, S0006–3223, 32342–32343 (2016)