Key signaling protein associated with addiction controls the actions of oxycodone in pain-free, chronic pain states
Using mouse models of acute and chronic pain, Mount Sinai researchers found that RGS9-2, the intracellular protein that controls the function of opioid receptors in the brain reward center, promotes addiction to oxycodone in pain-free, acute, and chronic pain states. Mice that lacked the gene responsible for encoding RGS9-2 (RGS9KO mice) showed less propensity to develop addiction-related behaviors. Furthermore, the loss of RGS9-2 function does not affect the acute analgesic effects of oxycodone. The research team also found that RSG9-2 plays a protective role towards the development of oxycodone tolerance, as RGS9KO mice became tolerant to the analgesic effects of the drug earlier than those that had the gene. Researchers found that the same mechanisms control sensitivity to oxycodone addiction in pain-free as well as chronic pain states. Oxycodone is a painkiller that is widely prescribed for acute and chronic pain conditions and is also among the most abused opioids. Oxycodone...