the parafascicular nucleus (pfn) of thalamus, as a supraspinal structure, has an important role in processing of nociceptive information. in addition, μ-opioid receptor contributes to supraspinal modulation of nociception. in the present study, the effects of microinjection of naloxone (a non-specific opioid-receptor antagonist) and naloxonazine (a specific μ-opioid receptor antagonist) were in...

The parafascicular nucleus (PFN) of thalamus, as a supraspinal structure, has an important role in processing of nociceptive information. In addition, μ-opioid receptor contributes to supraspinal modulation of nociception. In the present study, the effects of microinjection of naloxone (a non-specific opioid-receptor antagonist) and naloxonazine (a specific μ-opioid receptor antagonist) were in...

Opioid and opioid-like receptors are activated by a variety of endogenous peptides including [Met]enkephalin (met), [Leu]enkephalin (leu), β-endorphin (β-end), α-neodynorphin, dynorphin A (dynA), B (dynB), big (Big dyn), nociceptin/orphanin FQ (N/OFQ); endomorphin-1 endomorphin-2 also potential peptides. The Greek letter nomenclature for the opioid receptors, μ, δ κ, is well established, NC-IUP...

Background: Several studies have shown that the ethanol-derived metabolite salsolinol (SAL) can activate the mesolimbic system, suggesting that SAL is the active molecule mediating the rewarding effects of ethanol. In vitro and in vivo studies suggest that SAL exerts its action on neuron excitability through a mechanism involving opioid neurotransmission. However, there is no direct pharmacolog...

Background and Purpose The μ-opioid receptor (μ receptor) is the primary target for opioid analgesics. 7-transmembrane (TM) 6TM μ isoforms mediate inhibitory excitatory cellular effects. Here, we developed compounds selective 6TM- or 7TM-μ receptors to further our understanding of pharmacodynamic properties receptors. Experimental Approach We performed virtual screening ZINC Drug Now library us...

The generation of potent opioid analgesics that lack the side effects of traditional opioids may be possible by targeting truncated splice variants of the μ-opioid receptor. μ-Opioids act through GPCRs that are generated from the Oprm1 gene, which undergoes extensive alternative splicing. The most abundant set of Oprm1 variants encode classical full-length 7 transmembrane domain (7TM) μ-opioid ...

μ-Opioid agonists mediate their analgesic effect through GPCRs that are generated via alternate splicing of the Oprm1 transcript. While the majority of μ-opioids interact with receptors comprising the canonical 7 transmembrane (7TM) domain, a recently identified class of μ-opioids appears to require a 6TM domain variant. In this issue of the JCI, Lu and colleagues provide an in vivo proof-of-co...

Opioids are widely prescribed pain relievers with multiple side effects and potential complications. They produce analgesia via G-protein-protein coupled receptors: μ-, δ-, κ-opioid and opioid receptor-like 1 receptors. Bivalent ligands targeted to the oligomerized opioid receptors might be the key to developing analgesics without undesired side effects and obtaining effective treatment for opi...

Inhibition of forebrain μ-opioid receptor signaling by low concentrations of rimonabant does not require cannabinoid receptors and directly involves μ-opioid receptors. Micromolar concentrations of rimonabant directly inhibits delta opioid receptor specific ligand binding and agonist-induced G-protein activity. receptor ligand with high in vitro and in vivo agonist efficacy.