The effects of putative anxiogenic compounds (FG 7142, CGS 8216 and Ro 15-1788) on the rat corticosterone response.

The effects of FG 7142, CGS 8216 and Ro 15-1788, three compounds that are believed to produce anxiety by an action at benzodiazepine receptors in the CNS, are investigated on the plasma corticosterone concentrations in the rat both in the home cage and after exposure to novelty stress. FG 7142 (5 mg/kg) and CGS 8216 (10 mg/kg), but not Ro 15-1788 (4 or 10 mg/kg) increased basal corticosterone levels in the home cage, and all three compounds potentiated the increase in corticosterone concentrations observed after exposure to a novel environment. The relationship between the effects of drugs on corticosterone concentrations and on anxiety is considered in the light of these results.