Opioids mediate their effects via opioid receptors: mu, delta, and kappa. At the neuronal
level, opioid receptors are generally inhibitory, presynaptically reducing neurotransmitter …

Mu opioid receptor agonists are among the most powerful analgesic medications but also
among the most addictive. The current opioid crisis has energized a quest to develop opioid …

Ketamine, a racemic mixture of (S)-ketamine and (R)-ketamine enantiomers, has been used
as an anesthetic, analgesic and more recently, as an antidepressant. However, ketamine …

The κ-opioid receptor (KOR) has emerged as an attractive drug target for pain management
without addiction, and biased signaling through particular pathways of KOR may be key to …

Drug addiction is a worldwide societal problem and public health burden, and results from
recreational drug use that develops into a complex brain disorder. The opioid system, one of …

Rationale Accumulating evidence indicates that brain kappa-opioid receptors (KORs) and
dynorphin, the endogenous ligand that binds at these receptors, are involved in regulating …

Comorbidity is a major issue in psychiatry that notably associates with more severe
symptoms, longer illness duration, and higher service utilization. Therefore, identifying key …

The endogenous dynorphin-κ opioid receptor (KOR) system encodes the dysphoric
component of the stress response and controls the risk of depression-like and addiction …

Decades of research advances have established a central role for endogenous opioid
systems in regulating reward processing, mood, motivation, learning and memory …

Ample evidence has suggested the stress etiology of depression, but the underlying
mechanism is not fully understood yet. Here, we report that chronic social defeat stress …