These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Effect of nociceptin and [Phe1psi (CH2-NH) Gly2]-nociceptin-(1-13)-NH2 on tonic activity of rat hypothalamic neurons.
    Author: Yakimova KS, Pierau FK.
    Journal: Neurosci Lett; 1999 Oct 22; 274(2):87-90. PubMed ID: 10553944.
    Abstract:
    The effect of nociceptin, an endogenous ligand for a unique member of the cloned opioid receptor family ORL1-receptor, on tonic activity of neurons in the preoptic area/anterior hypothalamus (PO/AH) has been examined in rat brain slices using extracellular recordings. Nociceptin (1, 10 and 100 nM) decreased dose-dependently tonic activity of PO/AH neurons. This effect was not significantly different from the effect of [Phe1psi (CH2-NH) Gly2]-nociceptin-(1-13)-NH2 (1, 10 and 100 nM), recently proposed as a selective antagonist of the nociceptin receptor. Thus, [Phe1psi (CH2-NH) Gly2]-nociceptin-(1-13)-NH2 appears to be an agonist rather than an antagonist of nociceptin (ORL1) receptor in rat PO/AH neurons. However, there was neither antagonism nor additive synergism when nociceptin and [Phe1psi (CH2-NH) Gly2]-nociceptin-(1-13)-NH2 were applied simultaneously at equimolar concentrations. The effect of nociceptin on tonic activity of rat PO/AH neurons was not blocked by selective mu-, kappa- and delta-opioid receptor antagonists (D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP), nor-binaltorphimine and naltrindol, respectively) at 10 times higher concentrations than nociceptin. These data suggest that the effect of nociceptin on tonic activity of PO/AH neurons is not due to an action on mu-, kappa-, or delta-opioid receptors but results from a specific effect on the ORL1-receptor.
    [Abstract] [Full Text] [Related] [New Search]