Effects of pharmacological inhibition of the muscle myosin Ⅱ on mouse blastocysts
GUO Zheng1, DU Jing2, CHANG Cheng1
1. Institute of Developmental Biology, School of Life Sciences, Lanzhou University, Gansu, Lanzhou 730000, China; 2. Institute of Biomechanics and Medical Engineering, School of Aerospace, Tsinghua University, Beijing 100084, China
Abstract: Objective To explore the influence of ATP enzyme inhibitors (-)-Blebbistatin of non-muscle myosin Ⅱ（NM Ⅱ）on the blastocyst formation of mouse in vitro during early embryos and on the expression of pluripotent genes. Methods Ten of SPF class ICR strain female mice were induced by pregnant mare serum gonadotropin and human chorionic gonadotropin for superovulation. Female mice and male mice were caged with 1︰1.The morulae were taken from the uterus of the mice that have been pregnant for 0.5, 1.5, 2.5 days. Then the morulae were randomly distributed into the control group and the experimental group; drop culture of control group was 20 μl Ksom; that of experimental group was 20 μl Ksom added 25 μM (-)-Blebbistatin. After culturing in vitro for 24 hours, the morulae were labeled by immunofluorescence. The development of blastocysts was observed, and the expression of stemness genes of nanog, Oct4, sox2, ssea1 and estrogen was assessed. Results The development of early embryo in mice experienced increased number of blastomere after cell division, densification of morula and expansion of the blastocoel of blastula period. Embryo of (-)-Blebbistatin group could not formed into the blastocyst period, most of the embryo blastomere loosed and saddle shaped as a whole. The experiment was repeated three times. There were 62 embryos in the experimental group and all the blastocoel could not be formed. There were 60 embryos in the control group and all the blastocoel could be formed. After being treated by (-)-Blebbistatin, pharmacological inhibition of NM II, the gene expression of stemness genes of nanog, Oct4, sox2, ssea1 and estrogen, was significantly lower than that of the control group (P﹤0.05). Conclusion Inhibiting NM Ⅱ blocks the mouse blastocysts development and reduces the expression of pluripotent genes.
2017, Vol. 5 
