Pain is a multidimensional experience with sensory-discriminative, affective-motivational,
and cognitive-evaluative components. Pain aversiveness is one principal cause of suffering …

Drug addiction represents a dramatic dysregulation of motivational circuits that is caused by
a combination of exaggerated incentive salience and habit formation, reward deficits and …

Morphine and fentanyl are among the most used opioid drugs that confer analgesia and
unwanted side effects through both G protein and arrestin signaling pathways of μ-opioid …

The μ-opioid receptor (μOR) is a G-protein-coupled receptor (GPCR) and the target of most
clinically and recreationally used opioids. The induced positive effects of analgesia and …

Biased agonism at G protein–coupled receptors describes the phenomenon whereby some
drugs can activate some downstream signaling activities to the relative exclusion of others …

Biased agonism has been proposed as a means to separate desirable and adverse drug
responses downstream of G protein-coupled receptor (GPCR) targets. Herein, we describe …

Opioids are widely used as therapeutic agents against moderate to severe acute and
chronic pain. Still, these classes of analgesic drugs have many potential limitations as they …

Activation of the μ-opioid receptor (μOR) is responsible for the efficacy of the most effective
analgesics. To shed light on the structural basis for μOR activation, here we report a 2.1 Å X …

Abstract µ-Opioid peptide receptor (MOPR) stimulation alters respiration, analgesia and
reward behaviour, and can induce substance abuse and overdose,–. Despite its evident …

Opioids produce strong analgesia but their use is limited by a paradoxical hypersensitivity
named opioid-induced hyperalgesia (OIH) that may be associated to analgesic tolerance. In …