On the quantitative stereo-morphology of microbodies in rat hepatocytes

Employing the modified Sjöstrand technique for three-dimensional reconstructions from serial thin sections for electron microscopy, two populations of particles are described in rat hepatocytes. Analyses of nearly 500 particles in about 800 μm 3 of cytoplasm from three specimens revealed two morphological and size classes in a 2:1 ratio. A large class containing nucleoids is probably peroxisomal while a smaller class lacking nucleoids and bounded by a different limiting membrane may be peroxisomal, lysosomal or consist of particles not previously described.