MU-OPIOID RECEPTOR-BINDING IN INTACT SH-SY5Y NEUROBLASTOMA-CELLS

In order to determine affinities at the μ opioid receptor binding was conducted to intact SH-SY5Y neuroblastoma cells using the μ-selective ligand [3H][H-D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2] ([3H]CTOP). Binding appeared to be to a single receptor site, and a single state of the μ receptor. Under intact cell conditions, some but not all μ agonists display low affinity binding, while antagonists maintain high affinity for the μ receptor. These studies indicate the usefulness of [3H]CTOP for the determination of affinities at the μ receptor under physiological conditions. © 1990.