Summary
6-Fluoro-serotonin (6F-5-HT) was previously identified in the rat brain after peripheral administration of 6-fluoro-DL-tryptophan, a serotonin (5-HT) synthesis inhibitor. These present studies, performed with rat brain synaptosomes show that: i- neuronal 6F-5-HT uptake partly involved the 5-HT transporter since it was inhibited by clomipramine, a 5-HT uptake inhibitor, ii-6F-5-HT blocked the synaptosomal uptake of3H-5-HT, with an IC50 value of 98±13 nM, and iii- 6F-5-HT induced3H-5-HT release from preloaded synaptosomes, with an EC50 value of 95±6 nM; this release was decreased in the presence of clomipramine, suggesting the involvement of the 5-HT transporter. This release was also reduced when using synaptosomes from reserpinized rats, suggesting that the vesicular pool also participates to the3H-5-HT release induced by 6F-5-HT. So, 6F-5-HT behaved as a substrate for the 5-HT neuronal transporter.
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Chanut, E., Bonnet, J.J., Trouvin, J.H. et al. 6-Fluoro-serotonin as a substrate for the neuronal serotonin transporter. J. Neural Transmission 96, 105–112 (1994). https://doi.org/10.1007/BF01277932
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DOI: https://doi.org/10.1007/BF01277932