Stereospecific binding of morphine to phosphatidyl serine.
By measuring the adsorption of 14C-morphine to a surface film at an air-water interface, it was shown that morphine binds to phosphatidyl serine in a 1:1 molar ratio. With the use of levorphanol and the inactive d-isomer, dextrorphan, it could be demonstrated that the interaction was stereospecific. A Lineweaver-Burk plot disclosed that levorphanol and morphine competitively interacted with the lipid; the Km for morphine was 1.6 X 10(-5)M and the Ki for levorphanol was 4.8 X 10(-5)M. Heroin, a stronger opiate, had a greater affinity for phosphatidyl serine than did morphine or levorphanol.
D000327:Adsorption; D000818:Animals; D001923:Brain Chemistry; D002417:Cattle; D002855:Chromatography, Thin Layer; D003864:Depression, Chemical; D006017:Glycolipids / Q000378:metabolism; D007700:Kinetics; D050356:Lipid Metabolism; D009020:Morphine; D009022:Morphine Derivatives / Q000494:pharmacology; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010718:Phosphatidylserines / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism; D011955:Receptors, Drug; D013237:Stereoisomerism
D006017:Glycolipids; D009022:Morphine Derivatives; D010714:Phosphatidylethanolamines; D010718:Phosphatidylserines; D010743:Phospholipids; D011955:Receptors, Drug; D009020:Morphine