Abstract:To explore the effects of X-ray on weight,histological structure and expression of Bax protein in liver of developing filial mice,160 mice of 6~7 days after birth were radiated with different dosages (0, 1, 3, 5, 7Gy) of X-ray. Changes of liver and body weight were examined, histological structure was observed using bio-microscopy,and the expression of Bax protein was measured by immunohistochemical staining in filial mice liver at 1, 5, 10 and 20d after irradiation. Results show that X-ray influences the growth and development of the filial mice liver. The liver weight of filial mice of the experimental groups is lower than that of the control group 5~20d after irradiation (P<0.05 or P<0.01), except experimental groups with 1Gy; the body weight of filial mice of the experimental groups is lower than that of the control group 5~20d after irradiation(P<0.01); the expression intensity of Bax protein in the liver of filial mice is significantly increased with the increase of the dose; the structure of hepatic lobule is unclear, hepatic plate is thinner, hepatic sinusoid is stronger, accompanied with hepatocyte disfiguration, irregular arrangement, nucleus atrophy, and vacuolization, after irradiation.