Fig 1.
A. castellanii (2 × 105 cells) was incubated with various concentrations of drugs in PYG medium at 30°C for 48 h. After incubation, A. castellanii numbers were monitored by hemocytometer counting. A. castellanii incubated in PBS (nonnutrient) exhibited no growth, while A. castellanii incubated in PYG medium (growth medium) exhibited >8-fold increase in amoeba numbers from the original inoculum. All drugs tested showed significant inhibition of A. castellanii growth at the indicated concentrations (P < 0.01; paired t test; one-tail distribution). Among various drugs tested, prochlorperazine, haloperidol, and digoxin inhibited A. castellanii growth completely at 25 μg per ml. The results are representative of at least three independent experiments performed in duplicate. The data are presented as means and standard errors.