6-FLUORO-DL-TRYPTOPHAN

Biological Activity

6-fluoro-dl-tryptophan is a serotonin (5-ht) synthesis inhibitor.serotonin or 5-hydroxytryptamine (5-ht), a monoamine neurotransmitter, is biochemically derived from tryptophan. serotonin is primarily present in the gastrointestinal tract, blood platelets, and the central nervous system of animals. serotonin is considered to be a contributor to feelings of well-being and happiness.

in vitro

the potential competition was investigated between l-tryptophan (trp) and 6-fluoro-dl-tryptophan (6-f-trp). in equilibrium dialysis experiments, albumin bound about 80% of trp and 50% of 6-f-trp. competitive inhibition was assessed as the decrease in the apparent ka of trp in the presence of 6-f-trp, with no modification of the n value [1].

in vivo

rats werer administered 6-fluoro-dl-tryptophan (6f-trp) and its neurochemical effects on central catechole and indole were evaluated. results showed that neither norepinephrine nor dopamine and its major metabolites were affected by 6f-trp. with regard to serotonin (5-ht), 6f-trp could induce a transient depletion in all the studied brain areas, with a maximum of about 60-65% obtained between 1 and 3 hr. after 6 hr, 5-ht levels returned to control values. in addition, the 5-hydroxyindolacetic acid (5-hiaa) level was also reduced 3 hr after 6f-trp administration. a large dose-dependent increase in tryptophan was seen in the four brain areas, mainly due to an inhibition of tryptophan incorporation into protein, as demonstrated by experiments with mouse neuroblastoma cells [2].

references

[1] chanut, e. ,zini, r.,trouvin, j.h., et al. albumin binding and brain uptake of 6-fluoro-dl-tryptophan: competition with l-tryptophan. biochemical pharmacology 44(10), 2082-2085 (1992).[2] chanut, e. ,trouvin, j.h.,bondoux, d., et al. metabolism of 6-fluoro-dl-tryptophan and its specific effects on the rat brain serotoninergic pathway. biochemical pharmacology 45(5), 1049-1057 (1992).