Table 1

Glossary of terms for the compartmental model of E-Δ²-VPA and VPA distribution in the rabbit brain

C _b	Total concentration of drug in total brain tissue
C _b ^{^*}	Total concentration of labeled drug in total brain tissue
C _e	Concentration of drug in the extracellular fluid
C _e ^{^*}	Concentration of radiolabeled drug in the extracellular fluid
C _i	Concentration of drug in the intracellular space
C _in ^{^*}	Perfusate concentration of labeled drug entering the ventricles
C _out	Perfusate concentration of unlabeled drug in the cisternal outflow
C _out ^{^*}	Perfusate concentration of labeled drug in the cisternal outflow
C _p	Concentration of drug in the plasma water
C _v	Average concentration of drug in ventricular fluid
C _v ^{^*}	Average concentration of radiolabeled drug in ventricular fluid
f _e	Extracellular fractional volume of brain tissue
f _i	Intracellular fractional volume of brain tissue
K _ei	Rate constant for drug transfer from the extracellular fluid to the intracellular space
K _ep	Rate constant for drug transfer from the extracellular fluid to the plasma water
K _ev	Rate constant for drug transfer from the extracellular fluid to the ventricles
K _ie	Rate constant for drug transfer from the intracellular space to the extracellular fluid
K _pe	Rate constant for drug transfer from the plasma water to the extracellular fluid
K _ve	Rate constant for drug transfer from the ventricles to the extracellular fluid
Q	Perfusion flow rate of mock CSF through the ventricles
V _e	Volume of extracellular space
V _i	Volume of intracellular space
V _v	Volume of ventricular space