Chronic morphine impairs DOR internalization in HEK293/δ cells
| Surface DORs (% of total) | ||
|---|---|---|
| Control | Morphine pretreated | |
| Control | 60.1 ± 2.5 | 51.1 ± 3.3 |
| DADLE (1 hr; 1 μm) | 36.1 ± 0.4 (−39.9%) | 48.3 ± 3.5 (−5.4%) |
| Etorphine (1 hr; 100 nm) | 28.9 ± 0.7 (−51.9%) | 46.9 ± 4.0 (−8.2%) |
HEK293/δ cells were chronically treated with morphine (1 μm; 72 hr) before the effect of DADLE (1 μm; 1 hr) and etorphine (100 nm; 1 hr) on cell surface receptors was determined by [3H]diprenorphine binding. Results are the mean ± SEM from three separate experiments.