Effect of emetine and chloroquine on phagocytic processes of rat macrophages

Emetine and chloroquine caused a dose-dependent and time-dependent inhibition of bacterial phagocytosis in rat peritoneal macrophages. The effect of emetine was found to be stronger: 50% inhibition was achieved at 5 X 10(-6) M concentration. The inhibition of phagocytosis was irreversible. Neither the binding of bacteria to the surface of phagocytes nor membrane marker 5' nucleotidase was touched by this treatment. The adherence of macrophages to plastic dishes was also impaired by the drugs but only in a smaller extent. Both emetine and chloroquine blocked the amino acid incorporation into macrophage proteins. The effect of emetine was more marked; 10(-6) M decreased the incorporation to 25% of control, while 10(-4) M chloroquine produced a similar inhibition. The block of protein synthesis was also irreversible.