抄録
The early changes in the rat liver cells after the administration of ethyl chlorophenoxyisobutyrate (CPIB) were studied. At first, mitochondrial changes appeared 6 to 12 hours after the first dose of CPIB; the mitochondria were deformed and the succinic oxidase activity decreased; these changes disappeared in 24 hours. At 12 hours after administration an increase in smooth endoplasmic reticulum was observed and this proliferation reached the maximum on the 4th day accompanying increase of activity of drug metabolizing enzyme system. After 24 hours increased formation of microbodies without nucleoids followed the appearance of smooth ER and it was parallel to the increase of enzyme activities associated with microbodies, catalase and D-amino acid oxidase. These augmentations attained the plateau after 4 days. On the other hand, CPIB caused less remarkable change in lysosomes.
A consistent increase in the liver weight of rats receiving CPIB was found and this rise was not accompanied by any histological evidence of liver damages. easurements of protein, RNA and DNA show that the increase in liver weight is not due to the increase in the number of cells, but to the increase of the protein content in cytoplasm.
The relationship among intracellular organelles on the effect of CPIB was discussed.
