FIGURE 2. Cell uptake studies. (A) 8-[³H]GCV (GCV) and 8-[³H]PCV (PCV) net accumulation in C6 control and C6-stb-tk+ cell lines as function of time. (B) FGCV and FPCV net accumulation in C6 control and C6-stb-tk+ cell lines as function of time. Data are expressed as mean ± SE from triplicate samples. 8-[³H]PCV and FPCV show greater accumulation in C6-stb-tk+ cells compared with that of 8-[³H]GCV and FGCV.