Latrunculin a Enhances the Parthenogenetic Developmental Potentials of Electrically Activated Porcine Oocytes Matured In Vitro
The present study was carried out to determine the effect of latrunculin A (Lat-A) and FBS on the developmental potentials of electrically activated porcine oocytes maturedin vitro. Electrically activated MII oocytes were incubated for 2 hr in mPZM-3 supplemented either with 0、20 nM、1 μM Lat-A or 2.2 μg/ml cytochalasin B (CB). They were then removed and placed in mPZM-3 with or without 10% FBS (addition) on Day 4 for further development. The nuclear activation rate was significantly improved when activated oocytes were cultured in mPZM-3 with Lat-A (P<0.05). At higher dosage (1μM) of Lat-A, the extrusion of second polar body was inhibited while the cleavage rate increased significantly (P<0.05). Significant interaction between Lat-A and FBS supplementation on Day 4 was observed duringin vitrodevelopment (P<0.05). The hatched blastocyst rates and cell numbers per blastocyst were significantly enhanced with the supplementation of FBS (P<0.05). The blastocyst formation, hatched blastocyst rates and mean cell numbers per blastocyst of 1 μM Lat-A treatment with FBS supplementation were significantly higher than those of 20 nM Lat-A and CB treatments with FBS supplementation (P<0.05), but the individual effect of FBS supplementation was not observed on blastocyst formation in 20 nM and 1 μM Lat-A treatments. While significant difference was seen in blastocyst formation and cell numbers per blastocyst among all the treatments without FBS supplementation (P<0.05). These results indicate that Lat-A especially at the dosage of 1 μM can significantly improve the developmental potential of electrically activated porcine oocytes, and the FBS supplementation on Day 4 of development have an additional effect on porcine embryo development.