GABABreceptor subtypes IC50values of antagonists (μM). The drugs were tested against (−)-baclofen.
| Drug | Neurotransmitter Released | |||
|---|---|---|---|---|
| GABA | GLU | SRIF | CCK | |
| Rat cortex | ||||
| Phaclofen | 79.2 | >300 | 62.6 | 66.1 |
| CGP35348 | >300 | 4.2 | 3.6 | 3.5 |
| CGP52432 | 0.08 | 9.3 | 3.4 | 0.11 |
| CGP47656 | 3.1 | (Ago) | Ago | >300 |
| CGP36742 | >100 | >100 | 0.14 | >100 |
| Human cortex | ||||
| Phaclofen | ≈100 | >300 | N.D. | N.D. |
| CGP35348 | >100 | ≈10 | 24.4 | 13.9 |
| CGP52432 | ≪1 | >1; < 30 | 0.06 | 0.08 |
| CGP47656 | <10 | N.D. | Ago | Ago |
| CGP36742 | >100 | >100 | ≈5 | >100 |
GLU, glutamate; SRIF, somatotropin release-inhibiting factor; Ago, against; (Ago) partial agonist; CCK, cholecystokinin; N.D., not determined.