Table 1.
Density of receptors for the wild-type α1D-adrenoceptor and six gradually shorter trunctated α1D-adrenoceptor variants
| Transient expression in Neuro2A cells of wt and truncated α1D-adrenoceptors | A. Bmax receptors (fmol mg−1 protein) | B. Bmax receptors (% compared to wt) | C. pKd [3H]-prazosin | n |
|---|---|---|---|---|
| α1D-AR (wt) | 18.9±6.6 | 100 | 10.14±0.10 | 3 |
| Δ1–5α1D-AR | 10.3±3.3 | 56±12 | 10.12±0.13 | 3 |
| Δ1–17α1D-AR | 11.8±6.0 | 56±10 | 10.26±0.05 | 3 |
| Δ1–30α1D-AR | 34.7±18.3 | 156±39 | 10.40±0.00 | 3 |
| Δ1S–49α1D-AR | 106±75 | 426±198 | 10.32±0.06 | 3 |
| Δ1–58α1D-AR | 151±94 | 642±224 | 10.32±0.08 | 3 |
| Δ1–89α1D-AR | 52.6±27.2 | 238±57 | 10.32±0.02 | 3 |
The Bmax values were determined in Neuro2A cell membranes by [3H]-prazosin binding, following transient transfection of cells with 10 μg of construct DNA per 9 cm Petri dish. Column A shows the amounts of receptors (Bmax) in membrane preparations. Column B shows the Bmax in percent of the wt Bmax values, from experimentally paired plates. Column C shows the pKd values of [3H]-prazosin for the receptors.