Summary
The effects of the benzodiazepine (BDZ) receptor antagonist flumazenil (Ro 15-1788) and the GABAA receptor antagonist bicucuiline on the anticonflict effect observed after depletion of brain serotonin (5-HT), were examined in a modified Vogel's punished drinking conflict model. Pretreatment with para-chlorophenylalanine (PCPA; 300 mg/kg/day for three days, last injection −24 h) markedly decreased brain 5-HT levels and produced clearcut anticonflict effects. The anticonflict effect, but not the biochemical effect, of PCPA pretreatment was completely counteracted by both flumazenil (10 mg/ kg, −30 min) and bicuculline (2.0 mg/kg, −10 min), in doses not altering the behavior per se. The findings suggest a behavioral interaction between 5-HT systems and the GABAA/BDZ chloride ionophore receptor complex, possibly involving a direct neuronal interaction, neuromodulation or hormonal alterations.
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Söderpalm, B., Engel, J.A. Does the PCPA induced anticonflict effect involve activation of the GABAA/benzodiazepine chloride ionophore receptor complex?. J. Neural Transmission 76, 145–153 (1989). https://doi.org/10.1007/BF01578754
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DOI: https://doi.org/10.1007/BF01578754