Table 2.
Functional measurements of nAChR activity in α6-GFP mice. For the indicated measurement (Rb+ efflux, and DA release), brain regions were dissected, synaptosomes were prepared, and assays were conducted using ACh as agonist. For DA release, a range of ACh concentrations were tested (or 20 mM K+ as a positive control), results were fit to the Hill equation, and Rmax and/or EC50 values for ACh were derived and are shown. K+ results are total response (units are cpm normalized to baseline). For Rb+ efflux, three ACh concentrations (0.3 μM, 3.0 μM, 30 μM) were tested, and peak responses for each concentration are shown. For Rb+ efflux and DA release, αCtxMII-sensitive and resistant activity components are shown. For all experiments, data from groups of α6-GFP and control (non-transgenic) littermate mice were compared.
| DA Release (ACh) | control | α6-GFP |
|---|---|---|
| ST MII-res Rmax | 12.61 ± 0.51 | 12.04 ± 1.20 |
| ST MII-res EC50 | 1.01 ± 0.09 | 1.12 ± 0.32 |
| OT MII-res Rmax | 15.86 ± 0.77 | 13.63 ± 0.83 |
| OT MII-res EC50 | 0.44 ± 0.05 | 0.39 ± 0.06 |
| ST MII-sens Rmax | 3.34 ± 0.55 | 3.93 ± 0.29 |
| ST MII-sens EC50 | 0.18 ± 0.05 | 0.23 ± 0.04 |
| OT MII-sens Rmax | 4.32 ± 0.52 | 4.86 ± 0.75 |
| OT MII-sens EC50 | 0.11 ± 0.04 | 0.19 ± 0.06 |
| DA Release (K+) | ||
| ST K+ (20 mM) | 12.70 ± 1.29 | 10.61 ± 1.24 |
| ST K+ (20 mM) | 14.39 ± 0.35 | 12.69 ± 0.48 |
| Rb+ Efflux (ACh) | control | α6-GFP |
|---|---|---|
| SC MII-res (0.3 μM) | 1.08 ± 0.29 | 0.82 ± 0.13 |
| SC MII-res (3 μM) | 3.04 ± 0.54 | 2.26 ± 0.56 |
| SC MII-res (30 μM) | 3.52 ± 0.15 | 3.45 ± 0.14 |
| SC MII-sens (0.3 μM) | 0.85 ± 0.32 | 0.40 ± 0.26 |
| SC MII-sens (3 μM) | 1.53 ± 0.51 | 1.31 ± 0.43 |
| SC MII-sens (30 μM) | 4.01 ± 0.77 | 3.23 ± 0.74 |
ST: dorsal striatum; SC: superior colliculus; OT: olfactory tubercle. Data (units are cpm normalized to baseline) are mean ± SEM (n = 4–6 mice).