[Phospholipid exchange between mitochondria and microsomes of rat hepatoma 27]

The phospholipid exchange in vitro between mitochondria and microsomes from rat liver and rat hepatoma 27 was investigated. On incubation with a postmicrosomal protein fraction the phospholipid exchange between subcellular fractions of the tumor was found to proceed much faster and less specific than between mitochondria and microsomes from normal liver. These results indicate that the earlier demonstrated lipid dedifferentiation of tumor cell membranes may be connected with an altered transmembrane phospholipid exchange in vivo.