Table 4.
N/OFQ(1–13)–NH2 and [F/G]N/OFQ(1–13)–NH2 stimulation of GTPγ35S binding and inhibition of cAMP formation in CHOINDhNOP membranes and cells respectively, induced for 20 h with 1, 2, 5, 10 μM ponasterone A
| GTPγ35S | cAMP | |||||
|---|---|---|---|---|---|---|
| Induction (Ponasterone A) | pEC50/Emax N/OFQ(1–13)NH2 | pEC50/Emax [F/G](1–13)NH2 | N/OFQ(1–13)NH2/[F/G](1–13)NH2 | pEC50/Emax N/OFQ(1–13)NH2 | pEC50/Emax [F/G](1–13)NH2 | N/OFQ(1–13)NH2/[F/G](1–13)NH2 |
| 1 μM | 8.12±0.32 | Not analysable | — | Not analysable | Not analysable | — |
| 1.28±0.03 | ||||||
| 2 μM | 8.68±0.11 | 7.23±0.38 | 9.42±0.49 | 8.26±0.87 | ||
| 1.93±0.20 | 1.51±0.15 | 0.55 | 40.9±2.2 | 19.6±4.8 | 0.48 | |
| 5 μM | 8.52±0.06 | 7.68±0.10 | 9.72±0.40 | 8.99±0.18 | ||
| 4.33±0.80 | 2.01±0.23 | 0.30 | 79.5±4.1 | 59.37±5.8 | 0.75 | |
| 10 μM | 8.60±0.07 | 7.72±0.06 | 10.35±0.22 | 8.32±0.13 | ||
| 6.95±1.05 | 3.21±0.38 | 0.37 | 86.0±3.7 | 83.23±4.0 | 0.97 | |
Data are mean±s.e.m. for n⩾3 experiments. pEC50 values for N/OFQ(1–13)–NH2 and [F/G](1–13)–NH2 did not differ (P>0.05, ANOVA). There was a ponasterone concentration-dependent increase in Emax for N/OFQ(1–13)–NH2 and [F/G](1–13)–NH2 (P<0.05, ANOVA).