Table 1.
Compositions (in mM) of solutions used in oocyte electrophysiology.
Figure 1.
Effects of VU590 and VU608 on AeKir1 channels expressed heterologously in TREx-HEK293 cells.
(A) Chemical structures of the AeKir1 inhibitor VU590 and its ‘inactive’ analog VU608. Gray shading highlights the chemical differences between the molecules. (B) Concentration-response curves of VU590 (filled circles) and VU608 (open circles) derived from Tl+-flux assays. Values are means ± SEM. n = 2 independent experiments, each performed in triplicate. The calculated IC50 values for VU590 and VU608 are 5.6 µM (95% CI: 4.3–7.2 µM) and >100 µM, respectively.
Figure 2.
Effects of VU590 and VU573 on AeKir1 and AeKir2B channels expressed heterologously in Xenopus oocytes.
Current-voltage (I–V) relationships of representative AeKir1 (A, C) and AeKir2B (B, D) oocytes bathed consecutively in solutions containing 0.5 mM K+ (open boxes), 10 mM K+ (filled circles), and 10 mM K+ + 50 µM of a small molecule (gray circles). The small molecule is VU590 in panels ‘A’ and ‘B’, and VU573 in panels ‘C’ and ‘D’. (E) Summary of the percent changes of inward currents at −140 mV in AeKir1 and AeKir2B oocytes elicited by VU590 and VU573. Positive and negative percent changes indicate activation and inhibition, respectively. P values indicate significant activation or inhibition as determined by a one sample t test (on arcsine transformed values). Values are non-transformed means ± SEM. For VU590 experiments, n = 3 oocytes each for AeKir1 and AeKir2B. For VU573 experiments, n = 5 and 8 oocytes each for AeKir1 and AeKir2B, respectively.
Figure 3.
Effects of VU590 on the survival of adult female mosquitoes (A. aegypti).
(A) Dose-response curve of the toxic effects of VU590 on mosquitoes (R2 = 0.87). Mortality was assessed 24 h after injecting the hemolymph with 69 nl of the vehicle (K+-PBS50 with 15% DMSO, 1% β-cyclodextran, and 0.1% Solutol) containing appropriate concentrations of VU590 to deliver the doses indicated. The calculated LD50 is 1.56 nmol (95% CI: 1.29–1.88 nmol). Values are means ± SEM; n = 4 trials of 10 mosquitoes per dose. (B) Comparison of the toxic effects of the vehicle, VU590, and VU608. Mortality was assessed 24 h after injecting the hemolymph with the vehicle (K+-PBS75 with 15% DMSO, 1% β-cyclodextran, and 0.1% Solutol) or the vehicle containing a small molecule (2.8 nmol). Values are means ± SEM; n = 4 trials of 10 mosquitoes. Lower-case letters indicate statistical categorization of the means as determined by a one-way ANOVA with a Newman-Keuls posttest (P<0.05).
Figure 4.
Effects of VU590, VU608, VU573, and VU342 on the in vivo excretory capacity of adult female mosquitoes (A. aegypti).
(A) Amount of urine excreted by mosquitoes 1 h after injection with 900 nl of the vehicle (K+-PBS50 containing 1.8% DMSO, 0.077% β-cyclodextrane, and 0.008% Solutol), the vehicle containing VU590 (0.77 mM), or the vehicle containing VU608 (0.77 mM). Values are means ± SEM; n = 11 trials of 5 mosquitoes per treatment. Lower-case letters indicate statistical categorization of the means as determined by a one-way ANOVA with a Newman-Keuls posttest (P<0.05). (B) Same as ‘A’, but with VU573 and VU342. n = 9 trials of 5 mosquitoes per treatment.