[Ultrastructural study of lysosomes in rat pancreas in endotoxin shock--with reference to electron histochemical characterization].

: The ultrastructural alteration of Langerhans' islet cells as well as acinar structure in endotoxin shock was investigated in virtue of the electron histochemical procedures. One hour after administration of endotoxin, swelling and loss of cristae of the mitochondria, dilatation of the cisterna of the rough endoplasmic reticulum and swelling of the secretory granules in the B cell of Langerhans' islet cell were observed. On the contrary, the teleinsular acinar cells disclosed relatively intact ultrastructure, while the periinsular acinar cells showed in rather remarkable changes, such as the swollen mitochondria and obliteration of the rough endoplasmic reticulum. Four hours after administration of endotoxin, increase of the autophagic vacuoles in the cytoplasm of the acinar cells and in B cells of the Langerhans' islet cells were observed. Electron histochemical study disclosed the increase of rather small primary lysosomes in B cells of the Langerhans' islet cells, comparing to those of the acinar cells in normal condition. However, one hour after administration of endotoxin, acid phosphatase activity was activated and dispersed reactive substances were discernible in the cytoplasm of the B cells as well as intercellular and perivascular spaces.