People who were once addicted to drugs often end up dogged by memories associated with the addiction. Such memories tempt them to relapse, even after living drug-free for a number of years. However, a team of researchers at the Scripps Research Institute has found a way to selectively eliminate the memories associated with drug addiction.

The Scripps team says the findings can be useful in the formulation of a new therapy that can potentially help eliminate specific drug-associated memories. The researchers further say that the treatment is so effective that all other memories not associated with the drug addiction are left intact.

“We now have a viable target and by blocking that target, we can disrupt, and potentially erase, drug memories, leaving other memories intact,” said Courtney Miller, an associate professor at Scripps.

“The hope is that, when combined with traditional rehabilitation and abstinence therapies, we can reduce or eliminate relapse for meth users after a single treatment by taking away the power of an individual’s triggers,” said Miller.

During the study – complete details of which have been published in the journal Molecular Psychiatry – the researchers studied the effect of a single injection of an early drug candidate called blebbistatin in animal models. The animal models had methamphetamine addiction. Blebbistatin are small molecular inhibitors with a strong affinity for myosin II.

A single injection of blebbistatin acted on the actin protein present in the brain through nonmuscle myosin II, or NMII. Actin is a protein that helps provide a structural support to the memories in the brain, while NMII, a molecular motor, helps in memory formation. The study results showed that blebbistatin successfully disrupted the storage of drug-associated memories in the brain. In addition, it helped prevent relapse in animal models.

The recent research was based on findings of previous Scripps research that drug-associated memories can be successfully erased by specifically targeting the actin protein. However, since actin is essential for the brain and its complete inhibition could actually prove fatal, the research findings had no therapeutic use.