title: Interactions of codeine-7,8-oxide (codeine-epoxide), as a new metabolite of codeine, with multiple opiate receptors.
abstract: Interactions of codeine-epoxide, a new metabolite of codeine, with multiple opiate receptors were studied using radioligand binding assay. The ability of codeine-epoxide to displace [3H]dihydromorphine binding was the most effective among three labeled ligands, that is, [3H]dihydromorphine, [3H]-D-Ala2-D-Leu5-enkephalin and [3H]ethylketocyclazocine, suggesting that codeine-epoxide had a selectively high affinity to mu-receptors, despite the fact the affinities of codeine-epoxide to opiate receptors were slightly less potent than its parent compound, codeine. Since "sodium ratio" and "GTP ratio" on codeine-epoxide binding lay between those of codeine and naloxone, the interaction of codeine-epoxide with opiate receptors may be slightly different from that of codeine.
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D003061:Codeine / Q000031:analogs & derivatives* / Q000378:metabolism; D003496:Cyclazocine / Q000031:analogs & derivatives / Q000378:metabolism; D004090:Dihydromorphine / Q000378:metabolism; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000378:metabolism; D016308:Enkephalin, Leucine-2-Alanine; D016314:Ethylketocyclazocine; D006160:Guanosine Triphosphate / Q000494:pharmacology; D008297:Male; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects / Q000378:metabolism*; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D011957:Receptors, Opioid; D012965:Sodium Chloride; D016314:Ethylketocyclazocine; D004743:Enkephalin, Leucine; D016308:Enkephalin, Leucine-2-Alanine; C034035:codeine-7,8-oxide; D006160:Guanosine Triphosphate; D004090:Dihydromorphine; D003496:Cyclazocine; D003061:Codeine