"Top-Down" Mu-Opioid System Function in Humans: Mu-Opioid Receptors in Ventrolateral Prefrontal Cortex Mediate the Relationship Between Hedonic Tone and Executive Function in Major Depressive Disorder.

Cognitive dysfunction and anhedonia, the reduced ability to experience pleasure, are commonly comorbid symptoms that are persistent following successful resolution of negative affect in major depressive disorder (MDD). Little is known about whether they share common etiology. In the present study, the relationship between ventrolateral prefrontal cortex (VLPFC) activity, cognitive dysfunction (i.

Dopamine D2/D3 imbalance during migraine attack and allodynia in vivo.

Objective: To evaluate in vivo the dynamics of endogenous dopamine (DA) neurotransmission during migraine ictus with allodynia.

Methods: We examined 8 episodic migraineurs and 8 healthy controls (HC) using PET with [C]raclopride. The uptake measure of [C]raclopride, nondisplaceable binding potential (BP), would increase when there was a reduction in endogenous DA release.

Endogenous Opioid Mechanisms Are Implicated in Obesity and Weight Loss in Humans.

Context: Successful long-term weight loss is challenging. Brain endogenous opioid systems regulate associated processes; however, their role in the maintenance of weight loss has not been adequately explored in humans.

Objective: In a preliminary study, the objective was to assess central μ-opioid receptor (MOR) system involvement in eating behaviors and their relationship to long-term maintenance of weight loss.