[The effect and mechanism of estrogen on hepatocyte regeneration in rats]

Liver regeneration model following partial hepatectomy was used to study the effect and mechanism of estrogen on hepatocyte regeneration of rats. Each animal in the experimental groups received a single injection of diethylstilbestrol (DES) subcutaneously. Results showed that estrogen had a remarkable promoting effect on hepatocyte regeneration. Both 3H-TdR labelling and mitosis indices of hepatocytes in the experimental groups increased markedly. In DES-treated rats, synthesis of estrogen receptor of hepatocyte increased gradually and the translocation of ER from cytoplasm to nucleus was also enhanced at the same time, indicating that the mechanism of DES on hepatocyte regeneration consisted promoting of the interaction of ER and nucleus. There was no statistically significant difference (P greater than 0.05) found in the number of Kupffer cells between all the experimental and their corresponding control groups. But in ultrastructure, Kupffer cells of animals in the experimental groups presented increase of cell size with abundant cytoplasm; longer and more pseudopodia as well as phagolysosomes, suggesting that DES could activate Kupffer cell and promote its function. The relationship between Kupffer cells and liver regeneration is discussed.