Figure 8

Effects of purinergic inhibitor KN-62 on P. berghei erythrocyte invasion (A). Plasmodium berghei intraerythrocytic stages (ring, trophozoite or schizont) were assessed during an in vitro assay at time zero (beginning) (22.53 ± 2.93, n = 4; 73.21 ± 3.3, n = 4 and 3.26 ± 0.69, n = 4, respectively). (B) Culture of asynchronous P. berghei parasites were incubated for 17 h in the presence of DMEM (control), ATP (50 μM), ATP (50 μM) with DMSO (0.05%) or ATP (50 μM) with KN-62 (10 μM) and the parasitaemia calculated as a percentage of control (100, n = 4; 93.8 ± 9.3, n = 4; 84 ± 6.1, n = 7 and 80.2 ± 10.4, n = 9, respectively). Note no difference in erythrocyte invasion among the treatments (P > 0.05). Distribution of P. berghei intraerythrocytic stages in the presence of KN-62 (C). P. berghei intraerytrocytic stages: ring (41.9 ± 3.7, n = 9; 43.8 ± 3.6, n = 8; 45.2 ± 2.3, n = 9; 82 ± 4, n = 11; respectively), trophozoite (55.5 ± 3.8, n = 9; 53.7 ± 3.8, n = 8; 52.2 ± 2.5, n = 9; 18 ± 4, n = 11, respectively) or schizont (2.6 ± 0.4, n = 9; 2.5 ± 1, n = 8; 2.6 ± 1.1, n = 9; 0.00 ± 0.00, n = 11; respectively) were assessed after 17 h in the in vitro assay. Bars represents the number of rings, trophozoites and schizonts (average), expressed as a percentage of control ± S.E.M. Data were compared by one-way ANOVA and by the Newman-Keuls test. *Statistical significance with respect to control values P < 0.001.