The effects of ammonium ions and chloroquine on uptake and degradation of 125I-labeled asialo-fetuin in isolated rat hepatocytes

Abstract

The effects of NH 4 + and chloroquine on the uptake, the degradation and the intracellular distribution of 125I-labeled asialo-fetuin in isolated rat hepatocytes were investigated. Both ammonium ions and chloroquine inhibited asialo-fetuin degradation; chloroquine in high concentrations reduced uptake as well. Both compounds reduced the equilibrium density of the lysosomes in sucrose gradients. Labeled asialo-fetuin did not seem to accumulate in the lysosomes of cells exposed to NH 4 + or chloroquine. The possibility that both compounds retard the fusion between lysosomes and phagosomes is discussed.