Morphological changes in hepatic Ito cells after parenteral treatment with carmellose sodium in rats

Carmellose sodium (1.5%), dissolved in physiological saline, was given for 4 days via oral, subcutaneous or intraperitoneal routes. In the rats treated with carmellose sodium by the parenteral route, hepatic sinusoidal component cells and free macrophages were swollen. The degree of the swelling was more severe in the rats treated by the intraperitoneal route than by the subcutaneous route. The swollen sinusoidal component cells which engulfed the carmellose sodium-related substance were classified as Kupffer's cells or Ito cells by immunohistochemical reaction. Ito cells were isolated from a 5-week-old rat and were cultured in Dulbecco's modified Eagle's medium (DMEM). Some of the Ito cells which were cultured in DMEM containing 0.3% carmellose sodium showed phagocytic properties; vesicles in their cytoplasm and other Ito cells which were cultured in DMEM containing India ink contained some carbon particles.