TABLE 1

Relevant kinetic parameters of uridine uptake in HeLa cells

An unpaired t test was used to calculate kinetic parameters generated from three separate experiments (P < 0.05). A statistically significant difference between Kt and intrinsic clearance for ENT1- and ENT2-specific uridine uptake was found (P < 0.0001 for both). No statistical difference was observed for Jmax (P = 0.0699). All values are reported as mean ± S.D. of six replicate values (n = 3). * indicates P < 0.05

ENT1-Specific Uridine UptakeENT2-Specific Uridine Uptake
Jmax (pmol cm−2 min−1)16.53 ± 6.8830.40 ± 10.55
Kt (µM)13.60 ± 6.15*108.9 ± 15.74*
Intrinsic clearance Jmax/ Kt (μl cm−2 min−1)1.24 ± 0.07*0.28 ± 0.06*