Binding of [3H](+)-BW373U86 to delta-opioid receptors in rat brain membranes.
A tritiated form of the non-peptide delta-opioid receptor agonist (+)-BW373U86 ((+)-4-((alpha-R)-alpha-((2S,5R)-4-allyl-2, 5-dimethyl-l-piperazinyl)-3-hydroxybenzyl)-N,N-diethylbenzamide) was synthesized and its binding characteristics studied. [3H](+)-BW373U86 bound with subnanomolar affinity to rat brain membranes and was displaced most effectively by ligands selective for delta-opioid receptors. Naltrindole, naltriben, and 7-benzylidenenaltrexone exhibited apparent inhibition constants of 0.06, 1.54, and 4.49 nM, respectively, while mu- or kappa-selective ligands showed little affinity for this site. [3H](+)-BW373U86 binding was sensitive to the presence of guanine nucleotides; GDP caused a 3-fold decrease and 5'-guanylyl-imidodiphosphate (Gpp[NH]p) caused a 25% increase in binding affinity.
Campa
M J
MJ
Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
McNutt
R W
RW
Hill
J A
JA
Patz
E F
EF
Chang
K J
KJ
D000818:Animals; D001549:Benzamides / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D010879:Piperazines / Q000378:metabolism*; D051381:Rats; D017465:Receptors, Opioid, delta / Q000819:agonists; D013237:Stereoisomerism; D014316:Tritium
D001549:Benzamides; D010879:Piperazines; D017465:Receptors, Opioid, delta; D014316:Tritium; C083877:BW 373U86