NMDA-induced neuronal death in the presence of different mGluR ligands and NMDA receptor antagonists applied to mixed cortical cultures prepared from mGluR4 knock-out (KO, −/−) or wild-type (+/+) mice
| Compound | (Read-out) | % of NMDA-induced neuronal death | |
|---|---|---|---|
| mGluR4 KO (−/−) | Wild-type (+/+) | ||
| l-AP-4 | (trypan blue staining) | 103 ± 5 | 38 ± 3 |
| (LDH release) | 94 ± 8 | 41 ± 5 | |
| (R,S)-PPG | (trypan blue staining) | 98 ± 6 | 45 ± 5 |
| (LDH release) | 82 ± 12 | 55 ± 5 | |
| 4C3HPG | (trypan blue staining) | 63 ± 4 | 45 ± 5 |
| (LDH release) | 56 ± 9 | 36 ± 3 | |
| CPCCOEt | (LDH release) | 64 ± 16 | 79 ± 5 |
| MPEP | (LDH release) | 5 ± 5 | 32 ± 6 |
| MK-801 | (trypan blue staining) | 27 ± 4 | 12 ± 7 |
| (LDH release) | 18 ± 8 | 15 ± 3 | |
l-AP-4, (R,S)-PPG, and 4C3HPG were applied at a final concentration of 100 μm and CPCCOEt, MPEP, and MK-801 at 30, 3, and 10 μm, respectively. All compounds were coapplied with the NMDA pulse and were maintained in the medium for the following 24 hr. Values are means ± SEM of six to nine independent determinations.