5 Opioid receptor 193 binding sites

Quirion R., Pilapil C., Magnan J. Localization of kappa opioid receptor binding sites in human forebrain using [3H]U69,593 Comparison with [3H]bremazocine. Cell Mol. Neurobiol. 7 303, 1987. 

Hohmann AG, Herkenham M (1998) Regulation of cannabinoid and mu opioid receptor binding sites following neonatal capsaicin treatment. Neurosci Lett 252 13-16... 

Su, T.P. Evidence for sigma opioid receptor Binding of 3H-SKF-10,047 to etorphine-inaccessible sites in guinea-pig brain. J. Pharmacol Fxp Ther 223 284-290, 1982. 

Befort K, Tabbara L, Bausch S et al. The conserved aspartate residue in the third putative transmembrane domain of the <5-opioid receptor is not the anionic counterion for cationic opiate binding but is a constituent of the receptor binding site. Mol Pharmacol 1996 49 216-223. 

Xu H, Partilla JS, de Costa BR, Rice KC, Rothman RB. Differential binding of opioid peptides and other drugs to two subtypes of opioid deltancx binding sites in mouse brain further evidence for delta receptor heterogeneity. Peptides 1993 14 893-907. 

Rothman RB, Mahboubi A, Bykov V, Kim C-H, de Costa BR, Jacobson AE, Rice KC. Probing the opioid receptor complex with (+ )-trans-superfit. II Evidence that p ligands are noncompetitive inhibitors of the 6CX opioid peptide binding site. Peptides 1992 13 1137-1143. 

Narcotics function by binding to opioid receptors, specific sites on nerve cells in the brain and spinal cori The narcotic molecule, when bound to an opioid receptor, inhibits certain neurotransmitters involved in the transmission of pain impulses. 

The opioid peptides vary in their binding affinities for the multiple opioid receptor types. Leu- and Met-enkephalin have a higher affinity for 5-receptors than for the other opioid receptor types (68), whereas the dynorphin peptides have a higher affinity for K-sites (69). P-Endorphin binds with equal affinity to both p- and 5-receptors, but binds with lower affinity to K-sites (70). The existence of a P-endorphin-selective receptor, the S-receptor, has been postulated whether this site is actually a separate P-endorphin-selective receptor or is a subtype of a classical opioid receptor is a matter of controversy (71,72). The existence of opioid receptor subtypes in general is quite controversial although there is some evidence for subtypes of p- (73), 5-(74), and K-receptors (72,75), confirmation of which may be obtained by future molecular cloning studies. 

Carr DJJ, DeCosta BR, Kim C-H, Jacobson AE, Bost KL, Rice KC, Blalock JE (1990) Antiopioid receptor antibody recognition of a binding site on brain and leukocyte opioid receptors. Neuroendocrinology 51 552-560... 

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