C型钠肽预处理对牛卵母细胞体外成熟的影响

Effects of C-type Natriuretic Peptide Pretreatment on in vitro Maturation of Bovine Oocyte

旨在研究C型钠肽(C-type natriuretic peptide,CNP)预处理对牛卵母细胞体外成熟(In vitro maturation,IVM)的影响。以常规的牛卵母细胞体外24h成熟培养为对照,研究了CNP预处理牛卵母细胞6h,再进行成熟培养28h后(CNP预处理组)的牛卵母细胞成熟情况。结果表明,CNP预处理组的牛卵母细胞成熟效果明显提高,其受精后的囊胚率和囊胚细胞数都明显高于对照组((51.55%±2.50%),(156.2±11.0)和(28.13%±3.80%),(116.3±19.0),P<0.05);卵母细胞中线粒体分布由未成熟时的周边分布变为成熟时的均匀分布;而CNP预处理6h的卵母细胞中线粒体多呈半周边分布,在随后的28h成熟培养中也变为均匀分布;CNP预处理组的成熟卵母细胞线粒体DNA的拷贝数为(510 078.4±28 906.0),明显高于对照组的((416 558.5±51 743.0),P<0.05)。综上表明:C型钠钛预处理可以有效改善牛卵母细胞的体外成熟质量。

To study the in vitro maturation(IVM)of bovine oocyte pretreated with C-type natriuretic peptide(CNP).Compared with the conventional 24 hIVM culture,the effect of bovine oocytes pre-treated with CNP for 6hfollowing 28 hIVM culture(CNP pre-treated group)were studied.The results showed that the maturation of bovine oocyte in CNP pre-treated group were significantly improved,and the blastocyst rate and the cell number of blastocyst were significantly higher than those of the control group((51.55% ±2.50%),(156.2±11.0)vs.(28.13% ±3.80%),(116.3±19.0),P<0.05)after in vitro fertilization(IVF).The distribution of mitochondria ranged from peripheral distribution in unmatured oocyte to homogenous distribution throughout the cytoplasm in matured oocytes,while semi-peripheral distribution observed in the oocytes pretreated with CNP for 6h,but then became homogenous distribution followed 28 h maturation culture.The mtDNA copy number of matured oocyte in CNP pre-treated group were(510 078.4±28 906.0),which was significantly higher than that of control group((416 558.5±51 743.0),P<0.05).The results indicated that the quality of bovine oocytes in vitro maturation pre-treated for 6hwith CNP could be improved effectively.