磷酸二酯酶抑制剂对水牛卵母细胞减数分裂成熟的影响

Effects of pjosphodiesterase inhibitor on the meiotic maturation of buffalo cccytes

本研究探讨了磷酸二酯酶抑制剂米力农(milrinone)对水牛卵母细胞体外自发成熟和促性腺激素诱导成熟的影响,以便提高卵母细胞体外成熟质量。试验对水牛卵丘卵母细胞复合体(COCs)培养不同时间或采取不同处理后,取出卵母细胞剥光后固定,然后用间苯二酚蓝染色,观察卵母细胞核成熟情况。结果表明:(1)Milrinone对水牛COCs的自发成熟具有抑制作用,且具有剂量依赖关系;(2)Milrinone对水牛卵母细胞体外自发成熟的抑制作用随培养时间的延长没有减弱,可作为水牛卵母细胞成熟过程中的核成熟抑制剂;(3)Milrinone能显著抑制促卵泡激素(FSH)诱导的水牛COCs体外成熟,但是随着时间的延长,这种抑制作用可以部分被FSH克服。

In order to improve the in vitro maturation quality of oocytes, the present study was to investigate the inhibitory effect of milrinone on the spontaneous and FSH - induced meiotic maturation of buffalo oocytes. Buffalo cumulus-oocyte complexes （COCs） were obtained from the ovaries of prepubertal buffaloes and cultured in serum-free culture medium 199. Different treatments were carried out on the oocytes during the culture. At different periods, the oocytes were fixed and stained with lacmoid to observe the nuclear status. The incidence of ger- minal vesicle breakdown （GVBD） was examined at the end of the culture. The results indicated： （1） Milrinone, at the concentration of 25 100 μmol/L, could significantly inhibit the spontaneous maturation of buffalo COCs in a dose-dependent manner; （2） The inhibitory effect of milrinone on COCs was not decreased in a time-dependent manner within the 24-hour culture period, Therefore, milrinone is regarded as a nuclear maturation inhibitor for buffalo oocytes ; （ 3 ） Milrinone could significantly inhibit the FSH-induced maturation of buffalo COCs, however, the meiosis-arresting effect of milrinone on buffalo oocytes in this study was not overcome by addition of FSH to the culture media completely in a time-dependent manner.