Morphine-6beta-glucuronide rapidly increases pain sensitivity independently of opioid receptor activity in mice and humans. - van Dorp EL; Kest B; Kowalczyk WJ; Morariu AM; Waxman AR; Arout CA; Dahan A; Sarton EY; van Dorp, Eveline L A; Kest, Benjamin; Kowalczyk, William J; Morariu, Aurora M; et al. (Anesthesiology, 2009)