IC50 values for inhibition of DHβE-sensitive and DHβE-resistant 86Rb+ efflux
| Antagonist | DHβE-Sensitive Response IC50 | DHβE-Resistant Response IC50 |
|---|---|---|
| μM | μM | |
| Decamethonium | 4.1 ± 1.7 | 4.1 ± 0.4 |
| DHβE | 0.15 ± .05 | 8.3 ± 1.7 (DHβE) |
| 13.7 ± 3.3 (MLA) | ||
| Hexamethonium | 16.6 ± 6.1 | 0.89 ± .17 |
| Mecamylamine | 0.59 ± .09 | 0.16 ± .03 |
| MLA | 0.20 ± .06 | 4.4 ± 1.6 |
| dTC | 2.8 ± .7 | 1.1 ± .2 |
IC50 values were calculated by nonlinear least squares curve fits of the results shown in Fig. 7 using the equation: R = R0/(1 + I/IC50). The DHβE-sensitive response was measured for samples stimulated with 10 μM (−)-nicotine. The DHβE-resistant response was measured for samples stimulated with 10 μM (±)-epibatidine in the presence of 2 μM DHβE. IC50values for DHβE were also measured using 2 μM MLA. Values are mean ± S.E.M. estimated from the curve fits.