Effects of chloroquine on polyamines and nucleic acid of malaria parasites

Three polyamines-putrescine (PTC), spermidine (SPD), and spermine (SPM)—are found ubiquitously in low concentrations in erythrocytes (rbc) of animals. When mice were infected with P. yoelii or P. berghei, the contents of polyamines rose sharply. The polyamine levels in rbc infected with chloroquine(CQ)-resistant strain of were found to be PTC 27, SPD 513 and SPM 111 nmol/l09 rbc, respectively. In contrast, the polyamine levels in P. yoetii-infected rbc were lower (PTC 10, SPD l02 and SPM 20 nmol/l09 rbc). CQ inhibited the metabolism of polyamines in P. yoelii and CQ-sensitive strain of P. berghei, but not in CQ-resistant strain of P. berghei. After im CQ, the contents of DNA and RNA in malaria parasites remained unchanged, even though the metabolism of polyamines were significantly affected. By the Nakao’s method the recovery rate of rbc was higher (78%) and wbc was removed more effectively. Therefore, the Nakao’s method was better than the conventional method using CF-11 chromatography.