TABLE 3

Steady-state C_CSF/C_Plasma and C_ECF/C_Plasma ratios for each infusion step Data are shown as mean ± S.D. n = 6.

Infusion Step	C_CSF/C_Pt^a	C_CSF/C_Pu^b	C_ECF/C_Pt^a	C_ECF/C_Pu^b
1	0.4 ± 0.2^*	2.3 ± 1.2^*	0.4 ± 0.2^*	2.3 ± 1.5^*
2	0.4 ± 0.2^*	2.9 ± 2.3^*	0.4 ± 0.2^*	3.0 ± 3.9
3	0.5 ± 0.2^*	2.8 ± 2.4^*	0.4 ± 0.2^*	3.0 ± 3.8
4	0.5 ± 0.3^*	2.6 ± 1.6^*	0.4 ± 0.2^*	2.7 ± 2.2^*
5	0.5 ± 0.3^*	2.1 ± 2.0^*	0.5 ± 0.2^*	2.0 ± 2.4^*

↵ a The C_CSF/C_Pt ratios were calculated by dividing the concentrations of the last sample of CSF with the last sample of plasma in each step. The same procedure was applied to the calculation of C_ECF/C_Pt ratios
↵ b The C_CSF/C_Pu ratios were calculated by dividing the concentration of the last sample of CSF with the free plasma concentration (determined by equilibrium dialysis) of the last plasma sample in each step. The same procedure was applied to the calculation of C_ECF/C_Pt ratios
↵* Significantly different from the value of 1 (paired t test)