Anxiogenic drugs beta-CCE and FG 7142 increase extracellular dopamine levels in nucleus accumbens
Two experiments were conducted to study the effects of anxiogenic drugs on dopamine release and metabolism in nucleus accumbens. Microdialysis probes were implanted into the nucleus accumbens, and rats were tested the day after implantation. In the first experiment, groups of rats received injections of saline, 1.25 or 2.5 mg/kg beta-CCE. In the second experiment, groups of rats received injections of saline, 10.0, 20.0 or 30.0 mg/kg FG-7142. Both drugs produced significant increases in dopamine release and metabolism in nucleus accumbens. Neither drug had significant effects on locomotor activity. These experimeriments indicate that exposure to anxiogenic drugs increases accumbens dopamine activity, an effect that is consistent with other studies showing that the mesolimbic dopamine system is responsive to stressful stimuli. In addition, these results demonstrate that drug-induced increases in accumbens dopamine release are not unique to drugs of abuse.
Key wordsAnxiogenic drugs Beta-CCE FG 7142 Dopamine Nucleus accumbens Stress Microdialysis
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