The effect of various antagonists on the [35S]GTPγS binding
| D3 Receptors | ||
|---|---|---|
| IC50 (nM) | Imax (%) | |
| Haloperidol | 352 ± 49 | 100 |
| (+)-UH-232 | 434 ± 104 | 96 ± 4 |
| Raclopride | 1120 ± 220 | 94 ± 4 |
| (+)-AJ-76 | 438 ± 103 | 93 ± 3 |
| Clozapine | 540 ± 150 | 70 ± 8a |
The experiments were performed as described in “Methods.”
The results are means ± S.E.s of three to seven experiments. The inhibition (Imax) is expressed as percent of the maximal inhibition observed with haloperidol (100%) that was included in all experiments. The maximal inhibition was 55.9 ± 7.7 fmol/mg of protein (29 ± 2% over basal [35S]GTPγS binding) (n = 7). The basal [35S]GTPγS binding varied between 120–330 fmol/mg of protein. The D3 receptor density (Bmax) was 10700 pmol/g of protein in this series of experiments. Footnote indicates statistically significant difference compared with haloperidol (a P < .05).