Functional expression of opioid receptor-like receptor and its endogenous specific agonist nociceptin/orphanin FQ during mouse embryogenesis

摘要

Expression of opioid receptor-like receptor (ORL_1) and its endogenous peptide agonist nociceptin/orphanin FQ (N/OFQ) during mouse embryogenesis have been investigated. Transcripts of ORL_1 and N/OFQ were detected by RT-PCR in mouse brain of day 8 embryo (E8) and the expression continued afterwards. Northern blot analysis revealed abundant expression of ORL_1 at postnatal day 1 (P1) and N/OFQ at E17 and P1 in the brain but none was detected in other embryonic tissues. The presence of functional ORL_1in mouse embryonic brain was also confirmed by specific binding of [~3H] N/OFQ (kd=1.3 ± 0.5 nM and Bmax = 72 ± 9 fmol/mg protein) as well as by N/OFQ-stimulated G protein activation.