Reconstitution of partially purified opioid receptors with a GTP-binding protein.
Partially purified opioid receptors, obtained from rat brains using an affinity resin, AF-Amino Toyopearl with [D-Ala2, Leu5]enkephalin, were reconstituted with an inhibitory GTP-binding protein (Gi). In the reconstituted system, the displacement curve for the binding of a delta-agonist, [D-Ala2, D-Leu5]enkephalin, showed two states, high and low affinity binding ones, with different affinities for the agonist. The high affinity binding was eliminated by the addition of a guanine nucleotide analog to the system. These results directly showed that opioid receptors, at least the delta-type, could interact with Gi.
Fujioka
T
T
Faculty of Pharmaceutical Sciences, Mukogawa Women's University, Nishinomiya, Japan.
Inoue
F
F
Sumita
S
S
Kuriyama
M
M
D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism*; D002417:Cattle; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000378:metabolism; D016308:Enkephalin, Leucine-2-Alanine / Q000031:analogs & derivatives; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006165:Guanylyl Imidodiphosphate / Q000494:pharmacology; D007700:Kinetics; D051381:Rats; D011957:Receptors, Opioid / Q000302:isolation & purification / Q000378:metabolism*
D011957:Receptors, Opioid; D006165:Guanylyl Imidodiphosphate; D004743:Enkephalin, Leucine; D016308:Enkephalin, Leucine-2-Alanine; C030279:enkephalinamide-Leu, Ala(2)-; D019204:GTP-Binding Proteins