CdCl2对牛卵母细胞体外成熟及凋亡的影响

摘要

In this research,bovine oocytes were dealed with different concentration of CdCl2(0,0. 8,1. 6,2.4 g/mL) ,we detect the change of oocyte mature rate,Ca2+ distribution, apoptosis rates, the mitochondrial membrane potential, Bcl-2 and Bax gene expression, this study lay the foundation for the further research that is the influence of heavy metal to female mammals germ cell development and cell apoptosis mechanisms. Bovine oocytes were treated with different concentration of CdCl2 (0,0.8,1.6,2.4 |I,g/mL) for 22 h, we count the rate of maturity and apoptosis; The early apoptosis of bovine oocytes was detected by Annexin V-FITC;The change of Ca + distribution and the mitochondrial membrane potential were respectively detected by Fluo-3/AM and Rhl23;Using RT-PCR,we detected the relative expression of Bcl-2 and Bax. The mature rate and apoptosis rate of the bovine oocytes by 0. 8 g/mL treatment group compared with control group was not significant (P＞0.05) ;1. 6μg/mL and 2.4μg/mL treatment group compared with control group were not significant (P＜0.05) ;with the increase of concentration of CdCl2,Ca2+ fluorescence intensity in cytoplasm was increasing,the mitochondrial membrane potential gradually declined, Bcl-2 and Bax Relative ratio was descending. The induction of oocytes apoptos is by CdCl2 is dose effect, which can restrain oocytes mature and promote cell apoptosis.%利用不同浓度(0,0.8,1.6,2.4 μg/mL)的氯化镉(CdCl2)对处理牛卵母细胞前后对其成熟率、凋亡率、Ca2分布、线粒体膜电位、Bcl-2与Bax的基因表达的影响,初步为重金属对雌性哺乳动物生殖细胞发育及细胞凋亡机制的进一步研究打下基础.利用0,0.8,1.6,2.4 μg/mL的氯化镉(CdCl2)处理牛卵母细胞22 h,统计其凋亡率及死亡率；利用Annexin V-FITC检测牛卵母细胞的早期凋亡；分别用Fluo-3/AM和Rh123检测卵母细胞的Ca2+分布及其线粒体膜电位的变化；利用RT-PCR检测促凋亡基因Bcl-2和抑凋亡基因Bax的相对表达.经过上述处理后,0.8μg/mL处理组卵母细胞的成熟率和凋亡率与对照组相比差异不显著(P＞0.05),而1.6 μg/mL和2.4 μg/mL处理组与对照组相比差异显著(P＜0.05)；随着处理浓度的增加,胞浆Ca2+的荧光强度逐渐增强,线粒体膜电位逐渐下降,bcl-2与Bax 的相对比值下降.CdCl2诱导卵母细胞的凋亡呈剂量效应,可以抑制卵母细胞的成熟,促进细胞的凋亡.