Table 3.
Modulation of [3H]TCP binding to Torpedo nAChRs elicited by benzylidine-anabaseine analogues
| Benzylidine-anabaseine analogue | Apparent EC50a(µmol·L−1) | nHc | IC50b(µmol·L−1) | nHc |
|---|---|---|---|---|
| DMXBA | 3.9 ± 1.2 | 0.79 ± 0.03 | 172 ± 12 | 2.04 ± 0.25 |
| 4OH-DMXBA | 0.21 ± 0.02 | 1.37 ± 0.17 | 611 ± 65 | 1.91 ± 1.10 |
Data shown are the means ± SD, from two to three experiments each performed in triplicate.
BA concentration required to produce 50% binding enhancement as a measure of AChR desensitization. These values were obtained using nAChRs in the absence of any ligand (mostly in the resting but activatable state), from the portion of the plot where drugs enhance radioligand binding (Figure 7).
Drug concentration to produce 50% binding inhibition. These values were obtained using nAChRs in the resting state (in the presence of α-BTx), from the portion of the plot where drugs inhibit radioligand binding (Figure 7).
Hill coefficients.
[3H]TCP, [piperidyl-3,4-3H(N)]-(N-(1-(2-thienyl)cyclohexyl)-3,4-piperidine; 4OH-DMXBA, 3-(4-hydroxy-2-methoxybenzylidene)-anabaseine; α-BTx, α-bungarotoxin; BA, 3-(benzylidene)-anabaseine; DMXBA (or GTS-21), 3-(2,4-dimethoxybenzylidene)-anabaseine; nAChR, nicotinic acetylcholine receptor.