Localisation and pharmacological characterisation of [3H]bremazocine binding in the bovine adrenal medulla.
[3H]Bremazocine (5 nM), in the presence of excess unlabelled mu and delta opioid ligands labelled two anatomically distinct populations of binding sites in the bovine adrenal medulla; a high density over the peripheral adrenaline-containing region of the medulla and a lower density over the central noradrenaline-containing region. This non-mu, non-delta opioid binding was specific (diprenorphine sensitive) but did not appear to involve classical kappa (kappa 1), sigma or PCP binding sites being insensitive to high concentrations of dynorphin (1-13), 3-PPP or MK-801. A significant proportion of the binding at both locations was however sensitive to competition by U50,488H or metorphamide. These data provide further evidence to support the existence of multiple opioid binding sites in the bovine adrenal medulla.
Bunn
S J
SJ
Neuroscience Group, Faculty of Medicine, University of Newcastle, Shortland, N.S.W., Australia.
D000313:Adrenal Medulla / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D001345:Autoradiography; D001575:Benzomorphans / Q000378:metabolism*; D001667:Binding, Competitive; D002417:Cattle; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D004745:Enkephalins / Q000494:pharmacology; D007700:Kinetics; D011957:Receptors, Opioid / Q000032:analysis / Q000378:metabolism*; D017473:Receptors, Opioid, kappa; D014316:Tritium
D001575:Benzomorphans; D004745:Enkephalins; D011957:Receptors, Opioid; D017473:Receptors, Opioid, kappa; D014316:Tritium; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004743:Enkephalin, Leucine; C034318:enkephalin, Ser(2), Leu(5), Thr(6)-; C027248:bremazocine