Abstract:Objective: To establish an antral follicle culture system suitable for investigating oocyte maturation and ovulation in ICR mice, a strain of mice that are frequently used in biomedical research in China, and to study the effect of luteinizing hormone(LH) and epidermal growth factor(EGF) on induction of oocyte maturation and ovulation in this follicle culture system. Methods: Large antral follicles were dissected and cultured in vitro, oocyte maturation and ovulation in these cultured follicles were then induced by supplementation of LH and EGF to the culture medium. Results: The antral follicle culture system suitable for investigating oocyte maturation and ovulation in ICR mice was successfully established. In this culture system, treatment with LH or EGF alone was able to induce oocyte maturation and cumulus expansion in follicle-enclosed cumulus-oocyte complexes, whereas supplementation with both LH and EGF was necessary for induction of ovulation. Conclusion: LH/EGF induces oocyte maturation and ovulation in cultured large antral follicles of ICR mice.