Antimalarial agents, 2. Artesunate, an inhibitor of cytochrome oxidase activity in Plasmodium berghei.

The activity of the cytochrome oxidase, which is located in the plasma and the nuclear and the food-vacuole-limiting membranes as well as in the mitochondria of the trophozoites of Plasmodium berghei, was inhibited completely by sodium artesunate, an antimalarial drug, in vitro at 1 mM and in vivo at 100 mg/kg iv. This enzyme appears to be a target for the antimalarial mechanism of action of artesunate and qinghaosu.