FIG 7.
Effect of VGP-106 on the plasma membrane integrity of L. donovani. (A) The effect of VGP-106 on plasma permeability was determined by incubating promastigotes with or without 10 or 30 μM VGP-106 for 1 and 3 h at 28°C and then treating them with 2 μM Sytox green for 15 min at 28°C. Triton X-100 (0.05%) was used as a control for 100% permeabilization. Data are means ± SD from three independent experiments. Significant differences were determined using Student's t test (*, P < 0.01 versus controls). (B) The effect of VGP-106 on plasma membrane potential was determined by incubation with 30 μM compound for 3 h and then treatment with a 2 μM concentration of the specific plasma membrane potential probe DiBAC4(3) for 10 min at 28°C. Untreated parasites were used as the control, and treatment with 10 μM CCCP was used as 100% depolarization of the plasma membrane potential. Data are means ± SD from three independent experiments.