Figure 4.
(A). Depiction of the tyrosine pathway. (B). Analysis of tyrosine, L-dopa, dopamine, norepinephrine, and epinephrine measured from a known mass of stool (ng/mg wet feces weight) by LC-MS/MS reflecting in vivo levels of these neurotransmitters from germ-free and B. dentium mono-associated mice. (C). Concentrations of tyrosine, L-dopa, dopamine, norepinephrine, and epinephrine in a known mass of whole brain homogenate (ng/mg brain). For all experiments, n = 5 mice/group; two-way ANOVA, * p < 0.05.