This confocal microscope image shows midbrain neurons (red) co-expressing the mu-opioid receptor (Oprm1, white) and cannabinoid receptor 1 (Cnr1, green). The interaction of these two reward pathways ...

Scientists have known for decades that opioids relieve pain by binding to molecular switches in the brain called mu-opioid receptors. What they didn't know—until now—was exactly what happens next. A ...

By Artemis Molai Addiction is more likely to develop in certain brains than others. In studies reviewing families and heredity, approximately 50 to 60 percent of opioid use disorder risk is linked to ...