TABLE 2.
Comparison of the resting intracellular sodium concentration ([Na+]i) and the rate of increase and maximum increase in the [Na+]i after a 10-min exposure to 100 nM cipargamin in the P. knowlesi A1-H.1 parental and orthologue replacement lines and the P. falciparum 3D7 linea
| Parasite line | Resting [Na+]i, mM (P value) | Rate of increase in [Na+]i 10 min after cipargamin exposure, μM/s (P value) | Maximum increase in [Na+]i 10 min after cipargamin exposure, mM (P value) |
|---|---|---|---|
| Parental | 8.75 ± 1.54 (0.7587) | 23.3 ± 4.26 (0.9952) | 17.9 ± 3.23 (0.9974) |
| PkATP4ORb | 12.9 ± 2.48 (NA)b | 35.8 ± 9.98 (NA) | 26.2 ± 8.08 (NA) |
| PfATP4OR | 12.7 ± 2.67 (>0.9999) | 203.2 ± 54.1 (0.0002) | 138.6 ± 34.1 (0.0007) |
| PmATP4OR | 16.7 ± 2.43 (0.8913) | 35.7 ± 8.07 (0.9999) | 27.5 ± 6.59 (0.9999) |
| PocATP4OR | 22.0 ± 2.21 (0.0765) | 41.5 ± 8.85 (0.9997) | 35.4 ± 7.97 (0.9962) |
| PvATP4OR | 17.5 ± 2.81 (0.5835) | 96.6 ± 47.3 (0.2618) | 81.1 ± 39.9 (0.1312) |
| Pf3D7 | 6.34 ± 2.78 (0.3963) | 43.5 ± 4.84 (0.9996) | 33.3 ± 4.41 (0.9978) |
Resting [Na+]i, rate of increase, and maximum increase data were measured in SBFI-loaded saponin-isolated late-stage trophozoites suspended in physiological saline. All data show the mean ± SEM. Experiments for resting [Na+]i were performed in duplicate on at least three occasions, but some were performed up to eight times. Experiments for rate of increase in [Na+]i and maximum increase in [Na+]i were performed in technical duplicates performed on at least three biological repeats (up to five times). P values were calculated using ANOVA with Dunnett’s multiple-comparison test comparing the lines to the PkATP4OR line.
NA, not applicable (as this is the comparator line).