Ultrastructural and morphometric studies of normal rat hepatocytes.

Abstract

To investigate the arrangement of organelles in normal rat liver hepatocytes, we examined liver tissues by electron microscopy. We also analyzed hepatocyte organelles by morphometry using the NIH image software. The smooth ER area appears as a network of branching tubules and contains many glycogen rosettes. The rough ER area presents lamellar plates and contains free polyribosomes. The Golgi complex area comprises the parallel smooth surface of associated vesicles and contains secretory granules, lysosomes and a few glycogens. Ratio of the cross-sectional area of hepatocytes shows the smooth ER area (60 +/- SD 1.5%), the rough ER area (35 +/- SD 1.4%) and the Golgi complex area (4 +/- SD 1.7%) of the total cytoplasm. The rough ER shows a dendrite pattern in a hepatocyte. Many mitochondria are spread between the smooth ER and the rough ER area. The smooth ER directly communicates with the rough ER, the Golgi complex cisternae at a forming face and the nuclear envelope. Anastomosing tubules with polyribosomes between the smooth ER and rough ER, between smooth ER and the nuclear envelope frequently. These results provide a basics at the cellular level for better understanding the experimentally induced changes and for improving the pathological hepatic diagnosis.