[35S]GTPγS stimulation by maximum concentrations (10 μ M) of μ-opioid agonists in the thalamus of coronal brain slices of naïve rats
Values were determined using a concentration of 0.04 nM [35S]GTPγS as described under Materials and Methods and are presented as a percentage of maximum stimulation by DAMGO. Values represent the mean ± S.E.M. of three experiments each performed in duplicate.
| Drug | % DAMGO Maximum | |
|---|---|---|
| Male | Female | |
| Methadone | 58.5 ± 5.6 | 45.2 ± 9.6 |
| Fentanyl | 50.9 ± 7.3 | 59.4 ± 10.7 |
| Morphine | 42.8 ± 5.3 | 41.7 ± 8.1 |
| Heroin | 39.2 ± 5.9 | 42.8 ± 6.4 |
| Oxymorphone | 37.1 ± 6.4 | 35.4 ± 6.1 |
| Oxycodone | 36.6 ± 4.9 | 37.4 ± 4.5 |
| Codeine | 31.4 ± 5.2 | 25.5 ± 6.0 |
| Hydromorphone | 25.6 ± 4.9 | 34.3 ± 5.2 |
| Hydrocodone | 17.8 ± 5.8 | 20.3 ± 3.7 |