TABLE 3.
The impact of probenecid on pABA or folate-induced antagonism of antifolate activity in P. falciparum in vitro
Values are shown for assays carried out in folate and pABA-free RPMI-1640 media containing Albumax II. Supplements were present at 150 nm pABA, 25 nm 5-MTHF, and 0.5 nm FA. PBN was present at 150 μm. Values are presented as the mean ± S.D. n = 5–6. Probenecid significantly reduced the impact of supplementation on antimalarial drug activity (p < 0.01).
| Supplements | IC50 values |
|||
|---|---|---|---|---|
| SDX | SDX + PBN | PYR | PYR + PBN | |
| nm | pm | |||
| Control | 27.3±12.13 | 1.3±0.61 | 0.5±0.05 | 0.3±0.02 |
| pABA | 545±145 | 141±34 | 41.7±3.11 | 27.6±2.55 |
| 5-MTHF | 22.3±15.29 | 1.1±0.42 | 0.4±0.06 | 0.24±0.10 |
| FA | 31.7±22.23 | 1.5±0.35 | 0.35±0.06 | 0.22±0.03 |
| pABA + 5-MTHF + FA | 594±102 | 150±22 | 44.9±3.11 | 26.45±1.32 |