小鼠囊胚细胞凋亡和半胱氨酸天冬氨酸蛋白酶3表达与维甲酸的诱导作用

背景：细胞凋亡是维甲酸导致早期胚胎异常发育的原因之一,而半胱氨酸天冬氨酸蛋白酶3介导的细胞凋亡是细胞凋亡的主要途径。 目的：观察维甲酸对体外培养小鼠囊胚细胞凋亡的影响,以及对囊胚细胞中半胱氨酸天冬氨酸蛋白酶3表达的改变。 方法：获取妊娠3.5 d小鼠囊胚,分别在含0,1和10 μmol/L维甲酸的M199培养基中培养24 h,用带有荧光标记的原位末端标记法观察维甲酸对小鼠囊胚细胞凋亡的效应;并用免疫组织化学S-P法检测维甲酸对小鼠囊胚半胱氨酸天冬氨酸蛋白酶3的表达。 结果与结论：所有组均观察到囊胚细胞凋亡和半胱氨酸天冬氨酸蛋白酶3表达,高剂量维甲酸组中囊胚细胞凋亡荧光值,半胱氨酸天冬氨酸蛋白酶3表达的平均吸光度值和阳性面积率均显著升高(P < 0.01)。结果提示维甲酸可促进体外培养小鼠囊胚细胞凋亡和及半胱氨酸天冬氨酸蛋白酶3表达,证实了维甲酸对小鼠胚胎的发育的细胞毒性作用。

Induction effect of retinoic acid on cell apoptosis and Caspase-3 expression in mouse blastocysts

BACKGROUND:One of the reasons for abnormal development of embryos is the apoptosis induced by retinoic acid, and Caspase-3 mediated apoptosis is the main pathway for apoptosis in mouse blastocysts. OBJECTIVE:To observe apoptosis in mouse blastocyst induced by retinoic acid, and to detected expression of Caspase-3 in mouse blastocysts.  METHODS:Mouse 3.5 days blastocysts were exposed to doses of 0, 1 and 10 μmol/L retinoic acid for 24 hours. Effects of retinoic acid on mouse blastocysts apoptosis was observed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and the expression of Caspase-3 were detected by immunohistochemical S-P staining.  RESULTS AND CONCLUSION:Blastocysts apoptosis and Caspase-3 expression could be found in all groups, which was significantly higher in the high dosage group than that in the control and low dosage group (P < 0.01). The results suggest that retinoic acid can promote blastocysts apoptosis and Caspase-3 expression in vitro, confirm its cytotoxic effect on mouse embryos.