A Washington State University — Vancouver professor hypothesizes that blunting the drug-related memories of drug addicts can prevent them from seeking another hit, which could perhaps lead to addicts stopping drug use.

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One day, drug abuse may be less compulsive and users may be able to resist seeking another hit.

That scenario may become a reality, thanks to the research Barbara Sorg and her colleagues are conducting with rats like the one in her arms in a campus laboratory at Washington State University — Vancouver.

Sorg, a professor of neuroscience at WSU Vancouver, is working on the hypothesis that drug users develop drug-related memories: where they were, who they were with and what paraphernalia they used. Those memories evoke emotions that make it tough for the user to resist the drug.

Sorg hypothesizes that blunting the memories of drug addicts can prevent them from seeking another hit. Perhaps that could lead to addicts stopping drug use, she said.

But how do you blunt a memory? That’s what Sorg and her team of fellow researchers are doing with the rats.

Their research identified perineuronal nets surrounding neurons in the part of the brain that influences memory and learning.

Researchers believe the presence of nets can strengthen memories. Likewise, the absence of nets can weaken memories, Sorg explained.

“Certain brain cells have these nets surrounding them,” she said. “When those nets form, they make the memory not malleable. So we dissolve those nets to make the memory malleable.”

Researchers use a chemical to dissolve the net, thus weakening the drug memory, Sorg explained.

“Dissolving the nets is like hitting the reset button on the memory,” Sorg said.

Last month, her research was published in the Journal of Neuroscience.

This is the first time researchers have studied nets in the prefrontal cortex in relation to drug memories.

Other researchers are working on the same idea of blunting memories, but in regard to post-traumatic stress disorder, Sorg said. The background from altering memories started with fear and PTSD.

For this study, each rat’s cage has two compartments: a drug cage where rats receive a cocaine injection and learn to associate that place with the drug. In the second compartment, rats receive a placebo injection the following day. The rats addicted to cocaine seek out the drug cage.

Microphones in the drug cages capture the rat’s ultrasonic chirping. Happy noises.

“They like the cocaine,” Sorg said.

Drug users recall the memory every time they take cocaine.

For about six hours, the drug memory is labile, which means the memory can be disrupted, or changed, when it’s recalled, Sorg explained.

“Can we weaken that memory by doing some manipulation while it’s labile?” Sorg asked.

Her team of researchers uses pharmaceuticals to manipulate the memory of drug use. Rats with their nets removed via a pharmaceutical agent did not seek out the drug cage, she said.

“Removing the nets disrupts the memory at the time when they are labile,” Sorg said. “Each time they come out and get recalled, the memory can change,” she said.

Blunting the memories in human drug users has been done in a few other studies on other university campuses, she said.

Sorg’s study obtains the cocaine from the National Institute on Drug Abuse (NIDA), which is sponsoring the research. Researchers at Oregon Health and Science University and the University of Wyoming also are collaborating on the project.

Like all campus research with animals, the research is approved by WSU’s Institutional Animal Care and Use Committee.