Table 2.
Effects of flupirtine on TRPV1 channels, as well as ionotropic glutamate, GABAA, glycine and nicotinic acetylcholine receptors
| 10 µM flupirtine | 30 µM flupirtine | ||||||
|---|---|---|---|---|---|---|---|
| Agonist | Concentration | Normalized amplitude | n | P | Normalized amplitude | n | P |
| Capsaicin | 0.3 µM | 1.09 ± 0.05 | 5 | >0.05 | 0.98 ± 0.01 | 4 | >0.05 |
| 3 µM | 0.95 ± 0.06 | 5 | >0.05 | 1.03 ± 0.05 | 4 | >0.05 | |
| Glutamate | 3 µM | 0.98 ± 0.05 | 9 | >0.05 | 0.96 ± 0.07 | 9 | >0.05 |
| 100 µM | 1.05 ± 0.03 | 12 | >0.05 | 0.98 ± 0.04 | 12 | >0.05 | |
| NMDA | 10 µM | 0.89 ± 0.03 | 10 | >0.05 | 0.82 ± 0.03 | 10 | <0.05 |
| 100 µM | 0.87 ± 0.03 | 10 | >0.05 | 0.82 ± 0.04 | 10 | <0.01 | |
| GABA | 3 µM | 1.29 ± 0.09 | 6 | <0.05 | 1.45 ± 0.13 | 7 | <0.05 |
| 100 µM | 1.00 ± 0.04 | 8 | >0.05 | 0.98 ± 0.03 | 8 | >0.05 | |
| Glycine | 30 µM | 1.02 ± 0.05 | 5 | >0.05 | 1.04 ± 0.06 | 5 | >0.05 |
| 300 µM | 1.03 ± 0.02 | 5 | >0.05 | 0.97 ± 0.03 | 5 | >0.05 | |
| ACh | 10 µM | 0.88 ± 0.05 | 5 | >0.05 | 0.54 ± 0.12 | 5 | <0.01 |
| 300 µM | 0.98 ± 0.01 | 7 | >0.05 | 0.42 ± 0.04 | 7 | <0.001 | |
Currents were evoked by application of the indicated agonist concentrations in hippocampal neurons (glutamate, NMDA, GABA, glycine), DRG neurons (capsaicin), or in tsA cells expressing α3β4 subunits of nicotinic acetylcholine receptors (ACh). Normalized peak current amplitudes in the presence of 10 or 30 µM flupirtine were compared with those in the presence of solvent (not shown). P values for significances of differences versus solvent were calculated by a Kruskal–Wallis ANOVA followed by Dunn's post hoc test.