title: Morphine-like analgesic actions of enkephalin-like peptides containing the Tyr-Arg unit.
abstract: The analgesic actions of some synthetically prepared peptides having the Tyr-D-Arg unit at the N terminal portion of met- and leu-enkephalin were measured by the intra-cisternal injection method in mice. Among them, Tyr-D-Arg-Gly-Phe (DR-4) induced the most potent naloxone-reversible analgesia and was also effective by s.c. injection. DR-4 showed the good affinity to mu-receptor, and the resistance to the enzymatic degradation.
mesh_terms: D000818:Animals; D001120:Arginine; D001921:Brain / Q000378:metabolism*; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000378:metabolism; D016308:Enkephalin, Leucine-2-Alanine / Q000031:analogs & derivatives*; D004745:Enkephalins / Q000494:pharmacology*; D008297:Male; D009020:Morphine; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects / Q000378:metabolism*; D013329:Structure-Activity Relationship; D014443:Tyrosine
chemical_list: D004745:Enkephalins; D011957:Receptors, Opioid; D014443:Tyrosine; D004743:Enkephalin, Leucine; D016308:Enkephalin, Leucine-2-Alanine; C030279:enkephalinamide-Leu, Ala(2)-; D009020:Morphine; D001120:Arginine