己烯雌酚对雌性BALB/c小鼠脾细胞凋亡影响的动态观察

Dynamic observation of the effect of diethylstilbestrol on apoptosis of spleen cells in female BALB/c mice

目的了解新生期注射己烯雌酚(diethylstilbestrol,DES)对雌性BALB/c小鼠生后不同时期脾细胞凋亡及Bcl-2、Bax的影响。方法新生雌性BALB/c小鼠,在生后24h内颈背部皮下注射DES40μg,每隔24h注射一次,共连续5次,对照组平行注射等量无菌豆油。分别在生后7、14、21、35和49d将小鼠处死,取其脾进行常规石蜡包埋和切片,进行TUNEL(TdT-mediated dUTP nick endlabeling,)检测以及Bcl-2、Bax的免疫组织化学检测。结果与对照组相比,DES组雌性BALB/c小鼠脾细胞的TUNEL阳性细胞数目在生后各点均有显著性增加。Bcl-2在各时间点DES组的表达均弱于相应的对照组。Bax在生后7d的对照组和DES组中的表达差异无统计学意义,而在生后14、21、35和49d DES组的阳性表达明显多于对照组。结论新生期注射DES可以导致雌性BALB/c小鼠脾细胞凋亡明显增加。细胞凋亡在对照组和DES组不同时间点的动态变化以及在两组间相同时间点的差异可能与Bcl-2表达的减少以及Bax表达的增加有关。

Objective To investigate the effect of diethylstilbestrol（DES）on apoptosis and Bcl-2 and Bax of spleen cells in different postnatal period of female BALB/c mice treated with DES beginning in their neonatal period, Methods Neonatal female BALB/c mice were injected subcutaneously on cervix-backside with DES within 24 h after birth at intervals of 24 h for 5 times. Control groups were injected with axeinc bean oil with the same method. Mice were killed on day 7, 14, 21, 35 and 49 after birth separately, the spleens were taken out, imbedded with paraffin and sectioned serially in 5 ttm. TdT-mediated dUTP nick end labeling （TUNEL） assay for apoptosis and immunohistochemistry detection for the expression of Bcl-2 and Bax were performed. Results TUNEL assay showed more apoptostic cells in DES treated groups than in control groups at all time points after birth. On the contrary, the expressions of Bcl-2 were more in control groups than that in DES treated groups in all time points. Bax showed no difference between control groups and DES treated groups of mice on day 7 after birth, but showed more in DES groups than that in control groups of mice on day 14,21, 35 and 49 after birth. Conclusion Female BABL/c mice treated with DES beginning in their neonatal period results in significant increase of cell apoptosis in their spleen. The dynamic changes of cell apoptosis between control groups and DES treated groups at the different time point and the difference of cell apoptosis between the two groups at the same time point may be relevant to the decreased expression of Bcl-2 and the increased expression of Bax.