绵羊卵母细胞体外核成熟抑制及其对胚胎发育潜力的影响

自绵羊卵巢分离卵丘-卵母细胞复合物进行体外培养,培养基中分别加入或不加入抑制剂次黄嘌呤+dbcAMP或IBMX+dbcAMP。培养6h后各组取部分卵母细胞固定染色检查卵母细胞核成熟情况;将其余的卵母细胞分别移入无抑制剂的成熟培养基中继续培养18h后,再次检查各组卵母细胞核成熟情况,并进行体外受精和胚胎培养。结果表明:次黄嘌呤+dbcAMP或IBMX+dbcAM都分别能使60%以上的绵羊卵母细胞抑制在GV期。这种抑制是可逆性的,去除抑制剂后卵母细胞能恢复减数分裂,并加快由GVBD到MⅡ的成熟过程。各处理组受精率、卵裂率和囊胚发育率与对照组相比无显著性差异,表明卵母细胞的胚胎发育潜力没有受损。上述物质对卵母细胞成熟的可逆性抑制可用于研究卵母细胞成熟及其胚胎发育潜力的调节机制。

雌核发育银鲫和两性融合彩鲫卵母细胞体外诱导成熟过程中周期蛋白合成和MPF活性变化的比较研究

采用体外诱导卵母细胞成熟技术 ,比较研究了雌核发育银鲫和两性融合发育彩鲫卵母细胞成熟过程中周期蛋白合成和MPF活性变化情况。结果表明 :1 7α ,2 0 β 二氢孕酮(简称DP)浓度为 0 5μg/ml,温度为 2 4℃ ,光照时间 2 0小时为最适诱导条件。在相同条件下 ,两性生殖彩鲫卵母细胞体外诱导成熟速度明显快于银鲫。相应的细胞学研究表明 ,在体外诱导时 ,银鲫和彩鲫卵母细胞的发育成熟是正常的。银鲫卵母细胞生发泡破裂 (GVBD)时已有周期蛋白的合成 ,但生发泡破裂开始后则呈现合成速度下降直至没有

雌核发育银鲫和两性融合发育红鲤卵母细胞成熟的细胞学比较研究

对雌核发育银鲫和两性融合发育红鲤的卵母细胞成熟过程,进行了详细的细胞学比较研究。在银鲫卵母细胞成熟过程中,绝大部分卵母细胞的核物质,在胚泡破裂(GVBD)后的第一次成熟分裂时期,出现明显的不同于红鲤卵母细胞核的行为,其染色体逐渐清晰地分为三群,这三群染色体的发育既彼此独立又相互联系,最终形成一首尾相接的三极纺锤体。随后,三极纺锤体扭转、重叠、合并成为一个正常的中期纺锤体。但极少数银鲫卵母细胞也出现了类似于红鲤卵母细胞的成熟单星光,并进而发育成两极纺锤体,形态类似红鲤第一次成熟分裂中期纺锤体。在银鲫上述两类

INVOLVEMENT OF CA(2+) SIGNALING PATHWAY DURING OOCYTE MATURATION OF THE NORTHERN QUAHOG MERCENARIA MERCENARIA

In many molluses, it has been found that Ca2+ signaling pathway is involved in the resumption of meiotic maturation in oocytes. To better understand the possible role of Ca2+ signaling pathway in regulating meiotic maturation in oocytes of the northern quahog Mercenaria mercenaria, free extracellular Ca2+, A23187 (calcium ionophore), verapamil (calcium channel blocker), and trifluoperazin (calmodulin antagonist) were used to incubate oocytes or serotonin-induced oocytes by pharmacological methods. Results show that extracellular Ca2+ (50 similar to 200 mM) and A23187 (1 similar to 10 mu M) can stimulate the meiotic maturation. In addition, verapamil (1 similar to 100 mu M) and trifluoperazin (10 similar to 1,000 mu M) could inhibit serotonin-induced oocyte maturation. Therefore, Ca2+ is essential for the reinitiation of meiotic maturation in oocytes of the northern quahog. Moreover, an increase i [Ca2+]i can promote meiotic maturation.

Ovulação de matrizes de pacu Piaractus mesopotamicus e o papel da prostaglandina F2α

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Maturação nuclear de ovócitos de cadelas em estro e anestro submetidos à maturação in vitro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito de diferentes indutores hormonais sobre o processo de maturação final e ovulação em Leporinus macrocephalus

Pós-graduação em Aquicultura - FCAV

Influência da sazonalidade e da condição ovariana sobre a produção embrionária in vitro de gato doméstico (Felis catus, Linnaeus. 1758)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Time course of the meiotic arrest in sheep cumulus-oocyte complexes treated with roscovitine

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)