L-THP reduced OXA accumulation and attenuated OXA-induced
toxicity in primary DRG cells
Since OCT2 and MRP2 play vital roles in the uptake and efflux of OXA,
respectively, and L-THP strongly inhibited OCT2 activity but not MRP2,
we deduced that L-THP could reduce OXA accumulation and attenuate
OXA-induced toxicity in DRG. Our results revealed that 40 μM of OXA
significantly reduced the cell viability of primary DRG cells (to
approximately 52% of the control), while co-treatment with L-THP (1-100
μM) increased the cell viability in a concentration-dependent manner
(Figure 5a) ; for instance, 10 μM of L-THP increased the cell
viability to 75% of the control, which indicates that L-THP may reduce
the toxicity of OXA in DRG cells.
In agreement with the result of the cell viability test, L-THP (1-100
μM) reduced the accumulation of OXA in primary DRG cells in a
concentration-dependent manner; for example, L-THP at 100 μM reduced the
platinum accumulation in primary DRG cells to 32% of that in the
OXA-alone group (Figure 5b) . In summary, our results suggest
that L-THP can decrease the cellular accumulation of OXA and can thereby
ameliorate OXA-induced toxicity in primary DRG cells.