Ye Z G, Van Dyke K, Wimmer M
Department of Pharmacology and Toxicology, West Virginia University Medical Center, Morgantown 26506.
Exp Parasitol. 1987 Dec;64(3):418-23. doi: 10.1016/0014-4894(87)90055-5.
Using [G-3H]hypoxanthine uptake as a radioactive indicator for the growth of malarial parasites, we measured the antimalarial activity of artemisinin (Qinghaosu, QHS) against FCMSU1/Sudan strain (chloroquine-sensitive strain) and FCB K+ strain (chloroquine-resistant strain) of Plasmodium falciparum in continuous culture in vitro. The 50% inhibitory concentrations (IC50) for QHS against FCMSU1/Sudan strain and FCB K+ strain were 2.8 X 10(-8) and 3.0 X 10(-8) M, respectively. On the contrary, the response of the two strains to chloroquine was quite different. The IC50 for chloroquine against FCMSU1/Sudan strain was 5.6 ng/ml, whereas that for the FCB K+ strain was 65.6 ng/ml. Therefore, QHS did not appear to exhibit any cross-resistance with chloroquine. If [2,8-3H]adenosine was used as a radioactive precursor instead of [G-3H]hypoxanthine for the determination of antimalarial activity, virtually identical results were obtained. Therefore, [2,8-3H]adenosine can be used as an alternative to [G-3H]hypoxanthine for the assessment of antimalarial action.
以[G-3H]次黄嘌呤摄取作为疟原虫生长的放射性指标，我们在体外连续培养中测量了青蒿素（青蒿素，QHS）对恶性疟原虫FCMSU1/苏丹株（氯喹敏感株）和FCB K+株（氯喹耐药株）的抗疟活性。QHS对FCMSU1/苏丹株和FCB K+株的50%抑制浓度（IC50）分别为2.8×10（-8）和3.0×10（-8）M。相反，这两个菌株对氯喹的反应差异很大。氯喹对FCMSU1/苏丹株的IC50为5.6 ng/ml，而对FCB K+株的IC50为65.6 ng/ml。因此，QHS似乎没有表现出与氯喹的任何交叉耐药性。如果使用[2,8-3H]腺苷代替[G-3H]次黄嘌呤作为放射性前体来测定抗疟活性，则可获得几乎相同的结果。因此，[2,8-3H]腺苷可作为[G-3H]次黄嘌呤的替代品用于评估抗疟作用。
