Assertion: tryptophan | /r/CapableOf | cross the blood-brain barrier
Facets:
Source sentences:
text: Tryptophan has to cross the blood-brain barrier to develop its effect and improve the state of mind.
text: By sopping up other amino acids from the blood, however, insulin reduces the tryptophan's competition; the transport system is no longer tied up and more tryptophan can cross the blood–brain barrier.