Subcellular localization of acid lipase in rat liver

The intracellular localization of acid lipase was examined by several subcellular fractionation techniques. Upon differential centrifugation, acid lipase was detected mainly in the lysosomal fraction. When linear sucrose density gradient centrifugation was used, the mean density of acid lipase was similar to that of lysosomal marker enzymes. After Triton-treatment of rats, however, acid lipase was recovered at a density of 1.10-1.16, which is more than that of tritosomes, when tissues were homogenized with a Potter-Elvehjem homogenizer. But by homogenizing the liver from these rats by pressing it through a stainless steel net, acid lipase was mainly recovered at the same density as that of tritosomes. These results indicate that acid lipase is localized mainly in lysosomes in rat liver.