Ultrastructure of Plasmodium falciparum «in vitro». II: Morphological patterns of different quinolines effects

: In the present morphological study, we used electron microscopy (EM) to evaluate the activity of three quinolines upon Plasmodium falciparum strains cultured in vitro. The drugs (namely chloroquine, mefloquine and a new active substance, SF6606) showed common cellular targets (i.e. feeding process, protein synthesis, membrane formation and utilisation) but gave rise to different morphological features. EM as a tool is able to reveal a variety of drug-induced alterations, but it does not seem to supply evidence of a definite mechanism of action. Nevertheless, our observations suggest that each drug acts via several mechanisms, possibly linked to different degrees of parasite susceptibility.