Effects of phenylalanine on the release of endogenous dopamine from rat striatal slices

Entrez PubMed: "We conclude that phenylalanine is a less effective precursor of DA in rat striatum than tyrosine and that it can also act to inhibit DA synthesis, depending on its concentration." - J Neurochem. 1986 Nov;47(5):1444-8.

Now I'm looking at the studies to back up a phenylalanine-dopamine connection.