Abstract: 　Objective To induce a line of Plasmodium berghei with resistance to artemisinin. Methods The major methods included blood transmission from passage to passage and progressive increase of drug pressure. Results The resistant lines were developed by different protocols: A) The initial dosage of artemisinin was 126.2 mg/kg which was increased by 60 mg/kg for the next passage and boosted by 126.2 mg/kg for every other passage. As developed to passage 60 and 76, the resistant index was 18.39∶1 and 14.89∶1 respectively, then decreased gradually. For passage 108, the dosage was 8 862.5 mg/kg, but the resistant index was only 10.49∶1. B) Using passage 66 from A) as the source, a dosage of 4 000 mg/kg was given each week, the resistance of the passage 40 increased significantly with an index of 27.5∶1. C) Using passage 19 of B) as the source, drug was administered at the dose of 2 000 mg/kg each week. The resistant index of passage 15 was 17.41∶1. Conclusion Line of P.berghei with medium level resistance to artemisinin was established.

Key words: Plasmodium berghei, artemisinin, drug-resistance