Opioid pain relievers can be extremely effective in relieving pain, but can carry a high risk of addiction and ultimately overdose when breathing is suppressed and stops. Scientists have discovered a way to separate these two effects — pain relief and breathing — opening a window of opportunity to make effective pain medications without the risk of respiratory failure. The research, published today in Cell, was funded by the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health.
Opioid medications suppress pain by binding to specific receptors (proteins) in the brain; these same receptors also produce respiratory suppression. However, the way these receptors act to regulate pain and breathing may be fundamentally different. Studies using mouse genetic models suggest that avoiding one particular signaling pathway led to more favorable responses to morphine (pain relief without respiration effects). The investigators then explored if they could make drugs that would turn on the pathways associated with pain relief and avoid the pathways associated with respiratory suppression.