Influence of delta-opioid receptors on production of labeled methionine5-enkephalin in murine neuroblastoma cells.
Synthesis of methionine5-enkephalin by intact cells of murine neuroblastoma clone N1E-115 has been demonstrated both immunocytochemically and biochemically. In addition, N1E-115 cells possess homogeneous enkephalin (delta) receptors which inhibit prostaglandin E1-induced intracellular cyclic AMP formation. An assay was developed for measuring de novo synthesis of methionine5-enkephalin by pulsing cells in culture with radioactive methionine and isolating this pentapeptide to radiochemical purity by a procedure that included immunoaffinity chromatography specific for oxidized methionine5-enkephalin. This assay indicated that production of radiolabeled-methionine5-enkephalin was increased upon lengthy exposure of intact N1E-115 cells in the late logarithmic phase of growth to a nonproteolyzable analog of methionine5-enkephalin. This increase in synthesis of intracellular methionine5-enkephalin relative to control cells was prevented by prior incubation of the clone with naloxone, indicating that the response was mediated by the delta receptor.
Gilbert
J A
JA
Richelson
E
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D000818:Animals; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D003513:Cycloheximide / Q000494:pharmacology; D004744:Enkephalin, Methionine / Q000031:analogs & derivatives / Q000096:biosynthesis* / Q000378:metabolism; D051379:Mice; D009270:Naloxone / Q000494:pharmacology; D009447:Neuroblastoma / Q000378:metabolism*; D011691:Puromycin / Q000494:pharmacology; D011817:Rabbits; D011957:Receptors, Opioid / Q000378:metabolism*; D017465:Receptors, Opioid, delta; D013997:Time Factors
D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D009270:Naloxone; D011691:Puromycin; D004744:Enkephalin, Methionine; C022118:enkephalinamide-Met, Ala(2)-; D003513:Cycloheximide