Abstract: 　AIM: To isolate and quantitate chloroquine (CQ)-binding proteins in both CQ-sensitive (CS) AND CQ-resistant (CR) Plasmodium berghei . METHODS: P.berghei infected mice were each given ig CQ 400 mg/kg, respectively, 3 h later, the proteins of the parasites collected were separated using Ultrogel R AcA 34 gel column , followed by CQ extraction , the CQ concentration was determined by HPLC (extra standard). RESULTS: There were 58 protein peaks in the CS, all of which were bound with CQ,fraction Nos. 64～86 (peak 9) being the predominant, accounting for 16.4% of the total amount of CQ-binding protein. In the CR there were 40 protein peaks, among which 32 were bound with CQ, the predominant fraction Nos.60～83 (peaks 6,7),had a higher CQ-binding ability than CS. CONCLUSION: The distribution and amount of each CQ-binding protein peak in both CS and CR strains of P.berghei were demonstrated, exhibiting differences in the ability of CQ-binding not only between CS and CR strains but also within the same strain.

Key words: Plasmodium berghei, protein peak, chloroquine binding ability, AcA 34 column, HPLC