Effect of chloroquine on radiolabeled (¹²⁵ I) ferritin-protein degradation (A) and radioiron loss (B) from extracellular ferritin taken up by DEC. Incubations were performed for 0, 5, 20, and 44 hours. Other experimental conditions were as described in Figs 1 and 2. The intensity of the ferritin-label was measured by scanning with the phosphor imager. Means ± SD of 3 independent experiments.