Mad Science 2006 : Rats addicted to cocaine
Scientists at the University of Cambridge Department of Experimental Psychology investigated an experimental treatment for drug addiction. They surgically implanted fine plastic tubes directly into the brains of 100 adult rats and a second tube into their neck vein. The animals were made dependent by ‘rewarding’ them with cocaine when they pressed a lever. Some rats received up to 30 doses during three-hour daily testing sessions, which were carried out over 10 days. Several days after this, the rats were dosed with different combinations of two experimental drugs, administered directly into the brain, through the implanted tubes. The researchers wanted to see whether the drugs could block the memory of the rats, thereby abolishing their craving for more cocaine. At the end of the experiment, all the rats were killed and their brains examined. The researchers claimed to have chemically blocked the memory of craving in the brain of rats and suggested that it might be possible to do the same in human drug addicts.
Ref. Lee JLC, Milton AL, Everitt BJ. Journal of Neuroscience 2006; 26(22): 5881-5887. ‘Cue-induced cocaine seeking and relapse are reduced by disruption of drug memory reconsolidation.’