C型钠肽和半胱胺前成熟处理对牛卵母细胞发育能力的影响

Effect of Pre-IVM with C-type Natriuretic Peptide Combined with Cysteamine on Developmental Competence of in vitro-Matured Bovine Oocytes

本研究旨在探讨C型钠肽(CNP)结合半胱胺前成熟处理牛卵母细胞对其减数分裂和发育能力的影响。以常规的体外成熟24 h培养为对照,CNP前成熟(添加或不添加半胱胺)处理牛卵母细胞6 h,然后进行常规体外成熟培养,检测卵母细胞的成熟率以及体外受精后胚胎的卵裂率、囊胚率和囊胚细胞数。结果表明:与对照组相比,不论有无添加半胱胺,CNP前处理牛卵母细胞均未显著提高牛卵母细胞的成熟率和体外受精后的卵裂率(P>0.05),但显著提高了受精后囊胚细胞总数(P<0.05);CNP结合半胱胺前处理牛卵母细胞显著提高了受精后的囊胚率(P<0.05)。由此可见,CNP结合半胱胺前成熟处理牛卵母细胞提高了其发育潜能,可用于优化卵母细胞体外成熟培养体系。

The purpose of the present study was to investigate the effects of C-type natriuretic peptide(CNP)combined with cysteamine on meiotic maturation and developmental competence of bovine oocytes in vitro.Oocytes matured by standard IVM for 24 h(no pre-IVM)were used as the control.Oocytes were cultured in pre-IVM medium supplemented with CNP without or with cysteamine for 6 h,followed by standard IVM for 24 h.Subsequently,the maturation of oocytes,cleavage rates,blastocyst rates and the number of blastocyst cells were assessed.Results showed that although pre-IVM medium with CNP did not significantly increase the rate of bovine oocytes maturing to the metaphase II stage,cleavage rate after in vitro fertilization,but significantly improved the total number of blastocyst cells(P<0.05)compared with the control(standard IVM).Furthermore,the presence of cysteamine during pre-IVM with CNP further significantly improved the rate of embryos developed to the blastocyst stage after in vitro maturation and fertilization(P<0.05).In sumarry,the presence of CNP and cysteamine simultaneously during pre-IVM increased blastocyst rates,possibly indicating that the use of CNP combined with cysteamine during pre-IVM can be beneficial for estalishing a effective pre-IVM system aimed at modifying IVM system for enhancing the developmental potencial of bovine oocytes.