Electron Microscopy of Intracellular Protozoa.
Abstract
We studied the morphological effects of an antimalarial drug, mefloquine on Plasmodium berghei and Plasmodium falciparum by electron microscopy. Light microscopic examination of Giemsa-stained smears revealed morphological changes within 4 hours after drug administration. Initially small peripherally situated food vacuoles were noted within the parasites. With progressive enlargement, the vacuoles occupied up to 60-70% of the parasite volume. The degree of food vacuole swelling tended to increase the prolonged exposure time to mefloquine. Electron microscopy revealed enlarged food vacuoles with large amounts of finely granular matrix surrounding the pigment granules. No pigment granules are clumped together. By about 24 hours, concomitant degeneration of the nucleus and cytoplasm resulted in necrotic forms with dilated spaces where food vacuoles had been. These observations suggest that the mode of action of mefloquine is targetted on the parasite food vacuoles, similar to that of chloroquine. However, pigment clumping which has been described with chloriquine, was not observed. Neither drug appears to affect the merozoite stages of the parasite, which does not possess food vacuoles. Thus, mefloquine seems to interfere with parasite feeding and nutrition as does chloroquine.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1986
- Accession Number
- ADA178943
Entities
People
- Masamichi Aikawa
Organizations
- Case Western Reserve University