Table 1.
Compound | n | α3β4 | α3β4α5D | α3β4α5N | |
---|---|---|---|---|---|
Agonists | |||||
Nicotine | 8 | EC50 (μM) | 198 ± 26 | 149 ±11 | 531 ± 251# |
Rmax % | 88 ±5 | 36 ± 5** | 29 ± 3*** | ||
Acetylcholine | 6 | EC50 (μM) | 112 ± 28 | 89 ± 31 | 53 ± 21 |
Rmax % | 100 ± 10 | 73 ± 23 | 24 ± 6* | ||
Varenicline | 12 | EC50 (μM) | 24 ± 12 | 10 ± 2 | 36 ±26 |
Rmax % | 110 ± 9 | 69 ±4* | 32 ± 5*** | ||
Antagonists | |||||
Mecamylamine | 12 | IC50 (μM) | 1.18 ± 0.17 | 0.62 ± 0.09 | 0.44 ± 0.09** |
D-Tubocurarine | 12 | IC50 (μM) | 1.01 ± 0.24 | 0.94 ± 0.21 | 0.64 ± 0.15 |
Bupropion | 12 | IC50 (μM) | 0.67 ± 0.07 | 0.52 ± 0.07 | 0.38 ± 0.09* |
TMPH | 12 | IC50 (μM) | 0.83 ± 0.10 | 0.36 ± 0.02*** | 0.45 ± 0.04* |
Desensitization | |||||
Nicotine | 10 | IC50 (μM) | 0.7 ± 0.2 | 1.9 ± 0.7 | 0.8 ± 0.3 |
Results of the statistical tests: Kruskal–Wallis tests for EC50, IC50 and R max values: nicotine EC50 H = 8.405; p < 0.05, Rmax H = 15.77; p < 0.001; acetylcholine EC50 H = 2.558, p > 0.05, Rmax H = 7.797, p < 0.05; varenicline EC50 H = 0.4230; p > 0.05, Rmax H = 23.42; p < 0.001; mecamylamine IC50 H = 12.53; p < 0.01; d-tubocurarine IC50 H = 1.891; p > 0.05; bupropion IC50 H = 6.444; p < 0.05; TMPH IC50 H = 14.77; p < 0.001; nicotine desensitization IC50 H = 4.025; p > 0.05.
p < 0.05,
p < 0.01,
p < 0.001 α3β4 vs. α3β4α5D or α3β4α5N;
p < 0.05 α3β4α5D vs. α3β4α5N. Data are given as means ± SEM.