The dynorphin/kappa opioid receptor (KOR) system within the nucleus accumbens (NAc) contributes to affective states. Parvalbumin fast-spiking interneurons (PV-FSIs), a key component of feedforward inhibition, participate in integration of excitatory inputs to the NAc by robustly inhibiting select populations of medium spiny output neurons, therefore greatly influencing NAc dependent behavior. How the dynorphin/KOR system regulates feedforward inhibition in the NAc remains unknown. Here, we elucidate the molecular mechanisms of KOR inhibition of excitatory transmission onto NAc PV-FSIs using a combination of whole-cell patch-clamp electrophysiology, optogenetics, pharmacology, and a parvalbumin reporter mouse. We find that postsynaptic KOR stimulation induces long-term depression (LTD) of excitatory synapses onto PV-FSI by stimulating the endocytosis of AMPARs via a PKA and calcineurin-dependent mechanism. Furthermore, KOR regulation of PV-FSI synapses are input specific, inhibiting thalamic but not cortical inputs. Finally, following acute stress, a protocol known to elevate dynorphin/KOR signaling in the NAc, KOR agonists no longer inhibit excitatory transmission onto PV-FSI. In conclusion, we delineate pathway-specific mechanisms mediating KOR control of feedforward inhibitory circuits in the NAc and provide evidence for the recruitment of this system in response to stress.
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http://dx.doi.org/10.1038/s41386-021-01146-8 | DOI Listing |
Med Sci Monit
January 2025
Department of Anesthesiology, The General Hospital of Western Theater Command, Chengdu, Sichuan, China.
BACKGROUND Butorphanol, an opioid receptor agonist and antagonist, is widely used for post-cesarean section analgesia in the form of intravenous or intramuscular injection, but nasal sprays are less used. This study aimed to evaluate the analgesic effect of butorphanol nasal spray on uterine contraction pain after cesarean section and explore its effect on postpartum prolactin secretion. MATERIAL AND METHODS We randomly divided 120 patients scheduled for cesarean section into 3 groups (40 per group): intranasal saline (control), butorphanol intranasal (BI), and butorphanol pumped intravenously (BV).
View Article and Find Full Text PDFProg Neuropsychopharmacol Biol Psychiatry
January 2025
School of Psychology, University of New South Wales, Sydney, Australia. Electronic address:
The opioid crisis continues to escalate, disproportionately affecting women of reproductive age. Traditionally the first line of treatment for pregnant women with opioid use disorder is the mu-opioid receptor agonist methadone. However, in recent years, the use of buprenorphine as a replacement therapy has increased as it has fewer side-effects and longer duration of action.
View Article and Find Full Text PDFNeuroscience
January 2025
Institute for Neuroscience, The University of Texas at Austin, Austin, TX, USA; Waggoner Center for Alcohol & Addiction Research, The University of Texas at Austin, Austin, TX, USA; Department of Neuroscience, The University of Texas at Austin, Austin, TX, USA; Department of Neurology, Dell Medical School, The University of Texas at Austin, Austin, TX, USA. Electronic address:
While our understanding of the neurobiological mechanisms underlying cocaine and opiate reward has historically been dopamine-focused, evidence from genetic and pharmacological approaches indicates that µ-opioid receptors (MORs) in the striatum are important contributors. Within the striatum, MORs are expressed in both dopamine D1-receptor and D2-receptor expressing GABAergic medium spiny neurons (MSNs), as well as in interneurons and various afferents. Thus, it remains unclear how these distinct MOR populations regulate drug reward.
View Article and Find Full Text PDFDrugs Aging
January 2025
Center for Clinical Management Research, VA Ann Arbor Healthcare System, NCRC 016-308E, 2800 Plymouth Rd, Ann Arbor, MI, 48109, USA.
Background: Central nervous system (CNS)-active polypharmacy (defined as concurrent exposure to three or more antidepressant, antipsychotic, antiseizure, benzodiazepine, opioid, or nonbenzodiazepine benzodiazepine receptor agonists) is associated with significant potential harms in persons living with dementia (PLWD).We conducted a pilot trial to assess a patient nudge intervention's implementation feasibility and preliminary effectiveness to prompt deprescribing conversations between PLWD experiencing CNS-active polypharmacy and their primary care clinicians ("clinicians").
Methods: We used the electronic health record to identify PLWD prescribed CNS-active polypharmacy in primary care clinics from two health systems.
Mol Biotechnol
January 2025
Department of Urology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Opioids are the primary regimens for perioperative analgesia with controversial effects on oncological survival. The underlying mechanism remains unexplored. This study developed survival-related gene co-expression networks based on RNA-seq and clinical characteristics from TCGA cohort.
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