Differential feeding responses to Nociceptin/Orphanin FQ in Dark Agouti, Wistar Ottawa Karlsburg W and congenics DA.WOKW rats

Aim: We have previously demonstrated different sensitivity between DA and WOKW rats to the central hyperphagic effect of the Nociceptin/Orphanin FQ (N/OFQ) peptide. In this study we invistigated the effect of N/OFQ in congenics DA.WOKW to elucidate the genetic basis of N/OFQ-induced hyperphagia. Material and methods: DA.WOKW rats were generated as speed-congenics by a cross of WOKW and DA rats using marker-aided selection. The resulting cross hybrids were repeatedly backcrossed with DA using animals which were heterozygous at loci D3Mgh5, D3Rat1 (DA.3Wa) or D3Mit10, D3Rat189 (DA.3Wb) or D5Mgh6, D5Mit5 (DA.5W) or…