FIG. 6.

Effects of various drugs on L. mexicana amastigotes in axenic culture. Amastigotes (2 × 10⁵) were incubated with doubling dilutions of pentamidine (▪), allopurinol (□), aminopurinol (▾), and 5-fluorouracil (○) for 72 h and for an additional 48 h in the presence of Alamar blue reagent as described in Materials and Methods. Fifty percent effective doses for pentamidine as determined by fluorescence or cell counts (inset) were identical.