醋酸铅对小鼠卵巢颗粒细胞凋亡基因p53、Bax、Bcl-2表达的影响

将40只未成年雌性昆明系小鼠随机分成3个处理组和1个对照组,每组10只。处理组小鼠分别连续2 d腹腔注射铅10、20、40 mg/kg（按体质量给药）,对照组小鼠注射等体积的生理盐水。于注射后24、72 h分离卵巢,用原位末端标记法（TUNEL）测定卵巢颗粒细胞的凋亡率,同时用半定量RT-PCR方法检测凋亡基因p53、Bax、Bcl-2mRNA表达。结果表明,铅可促进颗粒细胞凋亡,且随剂量的增加和作用时间的延长,颗粒细胞中p53、Bax基因表达量逐渐增加,与对照组相比差异显著或极显著（P〈0.05或P〈0.01）;而Bcl-2基因表达量则逐渐减少（P〈0.05或P〈0.01）;表明铅可通过上调促细胞凋亡基因p53、Bax基因表达量,下调Bcl-2基因表达量,诱导卵巢颗粒细胞的凋亡。

Effect of lead acetate on the expression of p53,Bax and Bcl-2 in ovarian granulose cells of the mice

The 40 female kunming minor mice were divided randomly into 3 treatment groups and 1 control group with 10 each,The 3 treatment groups were injected intraperitoneal with 10,20 and 40 mg of lead per kilogram of body weight for 2 days,respectively,and the control group injected with the same volume of normal saline as the 3 treatment groups.The apoptosis rates of granulosa cells were detected by the TdT-mediated dUTP-biotin nick end Labeling（TUNEL） technique and preparation of paraffin section on day 1 and 3 post-injection respectively,meanwhile,the expression of p53,Bax and Bcl-2 gene in granulosa cells were detected by RT-PCR,in order to investigate the effect of lead on the expression of p53,Bax and Bcl-2 genes in ovarian granulose cells.The result dedicated that the apoptosis of granulosa cells treated with lead were accelerated,meanwhile the expression levels of p53 and Bax genes in granulosa cells increased gradually（P0.01 or P0.05） compared with that of control;but the expression level of Bcl-2 gene in granulosa cells decreased gradually（P0.05 or P0.01） with the increase of lead dosage and time,and which may be dependent on the dose and time.It is concluded that lead can induce the apoptosis of mouse ovarian granulosa cells through increasing the expression of p53 and Bax gene,reducing the expression of Bcl-2 gene in granulosa cells.