The Expression of Bcl-2 and Bax in Rat Hepatic Erythropoiesis

Chae, Hee Sun; Bach, Jae Hyung; Yoo, Seung Joo; Kim, Dae Jin; Kim, Sung Su; Kim, Kyung Yong; Lee, Won Bok

Abstract

Hepatic erythropoiesis is a characteristic event of the fetal liver. Generally, the erythropoiesis shows 4 phases: developing (embryonic day (ED) 10 to 14), maximum flat (ED 14 to 16), decreasing (ED 17 to 20), and disappearing day 1 to 10 after birth. In present study, TUNEL positive erythropoietic apoptotic cells were detected and increased through maximum flat phase, resulting in inducing decreasing phase. These results implicate that apoptosis is involved in the regulation of erythropoiesis in the fetal liver. Interestingly, the Bax over expressed in proerythroblasts and basophilic erythroblasts during developing phase, while Bcl-2 in polychromatic and acidophilic erythroblasts during decreasing phase. Moreover, in contrast to Bcl-2, Bax decreased from ED16, on which few erythropoietic cells were seen transiently. During disappearing phase, Bax increased by 2 to 3 times. But a rapid decline of Bcl-2 expression occurred on 1 day after birth. Thus, these results imply that the Bcl-2 and Bax play a role in proliferation and maturation of the erythropoietic cells by regulating apoptosis of the cells, in the hepatic erythropoiesis.