Benzomorphan binding sites in rat lumbo-sacral spinal cord.
The rat lumbo-sacral spinal cord contains a homogeneous population of opiate binding sites labelled with high affinity (KD = 0.21 +/- 0.04 nM) by [3H]etorphine and lower affinity (KD = 2.2 +/- 0.4 nM) by [3H]ethylketocyclazocine. Benzomorphan drugs are potent competitors for these binding sites while morphine and enkephalin display a low affinity. These binding sites have binding properties which are distinct from the mu-, delta-, and also kappa-sites but are very similar to those of the benzomorphan sites characterized in rat brain.
D000818:Animals; D001575:Benzomorphans / Q000378:metabolism*; D001665:Binding Sites; D003496:Cyclazocine / Q000031:analogs & derivatives / Q000378:metabolism; D016314:Ethylketocyclazocine; D005048:Etorphine / Q000378:metabolism; D066298:In Vitro Techniques; D007700:Kinetics; D008161:Lumbosacral Region; D008297:Male; D009019:Morphinans / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000378:metabolism*; D013116:Spinal Cord / Q000378:metabolism*
D001575:Benzomorphans; D009019:Morphinans; D011957:Receptors, Opioid; D005048:Etorphine; D016314:Ethylketocyclazocine; D003496:Cyclazocine