Reversal of the intrinsic effects of Ro 15-4513 on exploratory behavior by two benzodiazepine receptor antagonists.

In a holeboard test the imidazodiazepine Ro 15-4513 (1.5 and 3.0 mg/kg) reduced exploratory head-dipping. This effect was reversed both by the imidazodiazepine Ro 15-1788 (5 mg/kg) and by the beta-carboline ZK 93426 (2.5 mg/kg). These results indicate that the reduction in exploration caused by Ro 15-4513 is mediated by central benzodiazepine receptors.