brain levels of lysine , histidine , and some of the large neutral amino acids ( lnaas ) also exhibited clear relationships to the protein content of the test meal : those of valine , leucine , and isoleucine were depressed by the 0 % protein but increased ( compared with 0 % protein ) when protein was added to the meal : brain tyrosine was increased by all of the test meals in proportion to their protein contents ;
C0423896
content
C0006104
brain