Heme polymerase activity and the stage specificity of antimalarial action of chloroquine.
نویسنده
چکیده
Plasmodium falciparum lysate, prepared from 2.7 x 10(7) ring-infected erythrocytes and incubated with hemoglobin in sodium acetate at pH 5, incorporated a mean of 1.6 nmol of ferriprotoporphyrin IX (FP) into hemozoin in 18 to 22 hr. A similar preparation of trophozoite lysate incorporated a mean of 3.6 nmol of FP into hemozoin in 4 to 6 hr. These findings indicate differences between heme polymerase activity (hemozoin production) at the ring and trophozoite stages of malaria parasites. Intracellular hemozoin production was 90% inhibited at the ring and trophozoite stages by 0.5 and 7 nmol of chloroquine/10(6) infected erythrocytes. respectively. The inhibition killed the rings but not the trophozoites, suggesting that mature parasites may have a mechanism for protecting themselves against chloroquine-FP toxicity.
منابع مشابه
Clinical Pharmacology of the Antimalarial Chloroquine in Children and Their Mothers
Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium knowlesi are the parasites that infect humans. Plasmodium falciparum and Plasmodium vivax cause most of the malarial infections worldwide. Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium knowlesi are susceptible to chloroquine. Chloroquine was the world's most widely used antim...
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ورودعنوان ژورنال:
- The Journal of pharmacology and experimental therapeutics
دوره 282 1 شماره
صفحات -
تاریخ انتشار 1997