title: Enkephalin photoaffinity probes: synthesis and binding properties.
abstract: The diazomethyl ketone derivative of D-Ala2-Leu-enkephalin and Leu-enkephalin were synthesized. Replacement of the C-terminal carboxyl group with CO-CHN2 resulted in a potency decrease, the new compounds display micromolar affinities to 3H-naloxone and 3H-DALE binding sites. Photolysis of the ligands bound to rat brain membranes resulted in an approximately 30% irreversible loss of the receptors. Photoinactivation was prevented by the opiate antagonist, naloxone, thus providing that the ligands are specific photoaffinity probes of the opioid receptors.
authors.affiliation: Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, Szeged.
authors.forename: M
authors.initials: M
authors.lastname: Belcheva
authors.forename: G
authors.initials: G
authors.lastname: Csanady
authors.forename: M
authors.initials: M
authors.lastname: Szucs
authors.forename: E
authors.initials: E
authors.lastname: Varga
authors.forename: M
authors.initials: M
authors.lastname: Wollemann
authors.forename: K
authors.initials: K
authors.lastname: Medzihradszky
mesh_terms: D000345:Affinity Labels / Q000138:chemical synthesis* / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000378:metabolism; D016308:Enkephalin, Leucine-2-Alanine / Q000031:analogs & derivatives*; D004745:Enkephalins / Q000138:chemical synthesis* / Q000378:metabolism; D007202:Indicators and Reagents; D007700:Kinetics; D009270:Naloxone / Q000378:metabolism; D051381:Rats; D011957:Receptors, Opioid / Q000378:metabolism* / Q000528:radiation effects; D013329:Structure-Activity Relationship; D014466:Ultraviolet Rays
chemical_list: D000345:Affinity Labels; D004745:Enkephalins; D007202:Indicators and Reagents; D011957:Receptors, Opioid; D009270:Naloxone; D004743:Enkephalin, Leucine; D016308:Enkephalin, Leucine-2-Alanine; C030279:enkephalinamide-Leu, Ala(2)-