Abstract
l-Valine competes with tryptophan for transport into the brain and has previously been shown to decrease brain 5-HT synthesis. In the present study, the effect ofl-valine on electrically evoked hippocampal 5-HT release was determined in the anaesthetized rat using microdialysis. In control animals two electrical stimulations of the dorsal raphe nucleus 120 min apart (S1 and S2, respectively) released similar amounts of 5-HT. In contrast, in animals which receivedl-valine (200 mg/kg) between stimulations, S2 released a significantly smaller amount of 5-HT than did S1, although basal 5-HT release was unchanged. The data demonstrate thatl-valine decreases the electrically-evoked release of 5-HT in hippocampus in vivo.
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Gartside, S.E., Cowen, P.J. & Sharp, T. Evidence that the large neutral amino acidl-valine decreases electrically-evoked release of 5-HT in rat hippocampus in vivo. Psychopharmacology 109, 251–253 (1992). https://doi.org/10.1007/BF02245511
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DOI: https://doi.org/10.1007/BF02245511