Effect of acute delta-opioid receptor activation of [3H]forskolin binding parameters in NG108-15 cells
| Inhibitory ligand | PGE1-stimulated [3H]forskolin binding | ||
|---|---|---|---|
| EC50 (nM) | Emax(fmol/106 cells) | Kd (nM) | |
| None | 11.4 ± 2 | 19.9 ± 2 | 21.8 ± 4 |
| Morphine | 9.6 ± 5 | 21.2 ± 3 | 20.7 ± 6 |
| DSLET | 12.9 ± 6 | 18.3 ± 3 | 17.8 ± 10 |
High-affinity [3H]forskolin binding in intact NG108-15 hybrid cells was stimulated with increasing concentrations of PGE1 to determine EC50 and Emax values. The affinity of [3H]forskolin binding was determined from homologous displacement curves obtained in the presence of 10 μM PGE1. Reactions were done either in the absence of an inhibitory ligand or in the presence of morphine (10 μM) or the high-potencydelta-agonist DSLET (1 μM). Data are mean values ± S.D. of n = 3 experiments.