Abstract:

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.