Disrupting Memories Linked to Past Drinking May Reduce Alcoholic Relapse: Rat Study

Disrupting memories of past drinking, by blocking a pathway in the brain linked to learning and memories, may help reduce alcoholic relapse, a study of rats suggests.

Researchers at the University of California, San Francisco, inhibited activity of a signalling pathway in the brain of rats, called mTORC1, which disrupted their memories linked to past use of alcohol. The pathway controls the production of proteins linked with learning and memory, according to Nature.

The researchers exposed rats to a choice of water, or a mixture of water and 20 percent alcohol for a seven-week period. The rats were trained to press a lever to receive the alcohol.

Over time, the rats developed a strong preference for alcohol. The researchers then removed alcohol from the rats. After 10 days, they gave the rodents a tiny drop of alcohol, to reawaken their memories of it. Then some of the animals received the drug rapamycin, which inhibits mTORC1. The rats receiving rapamycin were much less likely to press the alcohol lever over a two-week period, the article notes.

The study appears in the journal Nature Neuroscience.

“One of the main causes of relapse is craving, triggered by the memory by certain cues – like going into a bar, or the smell or taste of alcohol,” lead author Segev Barak, PhD, said in a news release. “We learned that when rats were exposed to the smell or taste of alcohol, there was a small window of opportunity to target the area of the brain that reconsolidates the memory of the craving for alcohol and to weaken or even erase the memory, and thus the craving.”

The researchers said more data is needed to answer questions such as whether turning off mTORC1 with rapamycin could prevent relapse for longer periods. The drug is currently approved by the Food and Drug Administration to prevent organ rejection after transplantation.