The Effects of TGFα and EGF on Ovine Oocytes Maturation

Abstract: The effects of TGFα and EGF on nuclear and cytoplasm maturation of ovine oocytes cultured in basical medium + BSA， serum， BSA+EGF and BSA+TGFα respectively were investigated by immunofluorescence and orcein staining. The results showed that the maturation rate of oocyte cultured in the four medium as above after 22 hours were 63.5%， 75.2%， 73.1%， 69.8% and the rates of oocytes stayed at telophase of meiosis I were 27.0%， 16.3%， 15.9%， 16.9%， respectively. Supplement of serum， EGF or TGFα significantly enhanced the maturation rates of the oocytes and reduced the rate of oocyte stayed at telophase of meiosis I (P<0.05); Significant higher rates of normal distribution of α-tubulin in oocytes cultured in serum， BSA+EGF and BSA+TGFa (66.6%， 66.6%， 73.6%) were compared to BSA group (43.3%) (P<0.05); The rates of oocyte with cortical granules in cortex were 33.9%， 58.8%， 54.7%， 47.9%， respectively， there was significant difference between oocytes cultured with serum， EGF and BSA (P<0.05). In conclusion， TGFα and EGF can promote the oocyte nuclear transition from telophase I to metaphase of meiosis II， and could substitute some substance in serum to improve the quality of oocyte matured in vitro， but EGF might be more functional than TGFα to promote the maturation of ovine ooplasm.

CSTR: 32200.14.cjcb.2007.05.0018