or isomethadone or ketazocine or ketobemidone or ketogan or kyotorphin or lefetamine or levacetylmethadol or levomethadone or Levorphanol or Meperidine or Meptazinol or metazocine or Methadone or "Methadyl Acetate" or methylsamidorphan or Morphine or "morphinomimetic agent*" or "morphinomimetic drug*" or morphinone or Nalbuphine or narcotic* or nicocodine or nicomorphine or noracymethadol or norbuprenorphine
or Dihydromorphine or dimethylthiambutene or Diphenoxylate or dipipanone or enadoline or eptazocine or ethylketazocine or Ethylketocyclazocine or Ethylmorphine or etonitazene or Etorphine or etoxeridine or faxeladol or Fentanyl or furethidine or gelonida or Heroin or Hydrocodone or isalmadol or isomethadone or ketazocine or ketobemidone or ketogan or kyotorphin or lefetamine or levacetylmethadol or levomethadone
Comparison of the receptor binding characteristics of opiate agonists interacting with mu- or kappa-receptors. 1 The receptor binding characteristics of various morphine-like and ketazocine-like opiate agonists were measured by inhibition of [3H]-naloxone binding in homogenates of brain and of ileal myenteric plexus-longitudinal muscle of the guinea-pig. No differences were found for the two tissues. 2 The depressant effect of Na+ on the inhibition of [3H]-naloxone binding by opiate agonists varies widely, giving sodium shifts between 5 and 140. The relationship between Na+ concentration and inhibition of binding is non-linear, the magnitude of the sodium shift varying directly with the slope of the regression of log IC50 on log [NaCl]. 3 The sodium shift of ketazocine-like agonists
In the absence of morphine the inhibitory effects of the presynaptic alpha-adrenoceptor agonists, clonidine and oxymetazoline were much reduced and the dose-response curve was flat. This state of 'withdrawal' was readily reversed by morphine and levorphanol but not its inactive (+)-isomer, dextrophan. 3 The kappa-agonists, ketazocine and ethylketazocine, also restored the effects of clonidine as did the opioid
. Unique to each opioid is its distinct binding affinity to the various classes of opioid receptors (e.g. the μ, κ, and δ opioid receptors are activated at different magnitudes according to the specific receptor binding affinities of the opioid). For example, the opiate alkaloid morphine exhibits high-affinity binding to the μ-opioid receptor, while ketazocine exhibits high affinity to ĸ receptors