Figure 10.

DOPA addition can improve DOPA homeostasis when $j_5+j_{11}+j_{23}<j_7$. Panels a and b show reference calculations with two different $k_8$ values (representing different controller accuracies) when DOPA is not added ($k_{22}$ = 0 $\mathsf{\mu }$M/min). Panels c and d show the effect of DOPA additions. For all panels, (a–d): phase 1, no DOPA addition; phase 2, $k_{22}$ = 2 $\mathsf{\mu }$M/min addition; phase 3, $k_{22}$ = 4 $\mathsf{\mu }$M/min addition. Other rate constant values are as in Figure 9. Initial concentrations in panels a and c are as in Figure 9c. Initial concentrations in panels b and d are as in Figure 9b.