Figure 3: (A) Uptake of [3H] lopinavir (0.5 ╬╝Ci/mL) on LS180 cells post treatment with vinblastine alone and in the presence of optimized concentration of ritonavir. (B) Percentage CYP3A4 activity as estimated by formation of fluorescent substrate from LS180 cells post treatment with vinblastine alone and in the presence of optimized concentration of ritonavir. Values represent mean ± standard SD (n=4). A P-value of less than 0.05 was considered to be statistically significant and represented by *.