Referenced in: none

Automatically associated channels: Kir2.1 , Kir3.1

Title: Effects of sigma ligands on the nociceptin/orphanin FQ receptor co-expressed with the G-protein-activated K+ channel in Xenopus oocytes.

Authors: T Kobayashi, K Ikeda, S Togashi, N Itoh, T Kumanishi

Journal, date & volume: Br. J. Pharmacol., 1997 Mar , 120, 986-7

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/9134206

Abstract
Taking advantage of the functional coupling of the nociceptin/orphanin FQ receptor with the G-protein-activated inwardly rectifying K+ (GIRK) channel, we investigated the effects of various sigma ligands on the nociceptin/orphanin FQ receptor in Xenopus oocytes co-injected with the cloned nociceptin/orphanin FQ receptor and GIRK1 mRNAs. Carbetapentane and rimcazole, which induced no current response at 100 microM, reversibly suppressed the inward K+ current responses induced by nociceptin in a concentration-dependent manner, and the IC50 values (microM) for these compounds were 9.0 and 12.6, respectively. (+/-)-N-allylnormetazocine. (+)-cyclazocine, (+)-3-(3-hydroxyphenyl)-N-(1-propyl)piperidine and 1,3-di-(2-tolyl)guanidine, at 100 microM, had no effect on the receptor. These results suggest that carbetapentane and rimcazole act as antagonists at the nociceptin/orphanin FQ receptor and may be involved in pain regulation.