Light — not pain-killing drugs — used to activate brain’s opioid receptors

Washington University School of Medicine neuroscientists, led by Michael R. Bruchas, PhD, assistant professor of anesthesiology and of neurobiology, have attached the light-sensing protein rhodopsin to opioid receptor parts to activate the receptor pathways using light from a laser fiber-optic device. They also influenced the behavior of mice using light, rather than drugs, to activate the reward response.