ELECTRON MICROSCOPICAL INVESTIGATION OF MUSCLE CAPILLARIES APPLYING FREEZE-ETCHING TECHNIQUE

The structure of muscle capillaries in the mouse diaphragm was investigated applying the freeze-etching technique. The replicated fine structure has its equivalent in the cell components already known from ultra-thin sections. The particular advantage of the freezeetching technique is the possibility to examine the tissue structure in three dimensions. The study of large areas of membrane surfaces shows that the membrane is composed of particles. The different structures of the inner and outer surfaces indicate further the bipolarity of the unit membrane. In the erythrocyte membrane, both the inner and the outer surfaces are distinguished by their different structures and the characteristic distribution and size of their particles. The cytoplasm of the erythrocyte is filled with particles which might be hemoglobin molecules. The results of this paper and the findings of other workers are discussed. © 1969 Springer-Verlag Berlin Heidelberg.