The current concept of the regulation of ovarian function involves not only classic endocrine regulation, but also intraovarian regulation in the form of autocrine and paracrine control. In response to the natural luteinizing hormone(LH) surge,
follicular inhibition is overcome and maturation of the oocyte is stimulated to the stage of secondary oocyte with first polar body which is receptive to fertilization.
Among various chemical factors consisting of a positive signal to stimulate follicular maturation, the use of epidermal growth factor (EGF) may allow for the performance of successful in vitro fertilization procedures using immature oocytes
retrieved
during unstimulated cycles and the use of FSH could allow to maintain or increase growth factor stimulating follicular maturation whereas LH has no effect.
The objective of this study was to evaluate a direct modulatory action of FSH on the porcine granulosa cell culture and indirectly to obtain the imformation on the immature human oocyte culture in in vitro fertilization programs.
Porcine granulosa cells were collected from medium sized ovarian follicles. 2×10E5 viable cells were seeded in each fetal calf serum (FCS)-coated wells and cultured in 1 ml of DMEM/F-12 supplemented with 5μg insulin, 5μg transferring, 10ng EGF
and
100ng FSH per ml under 5% CO, 95%air at 37℃.
Determination of protein amounts of cultured granulosa cells was done by using Bio-Rad protein microassay.
The mean protein amount by cultured granulosa cells in FSH-treated group ws 63.3μg/ml and was much higher than that (19.3μg/ml) of basal media group after 24 hour culture.
In 72 hour culture, the mean protein of cultured granulosa cells in FSH-treated group was 250μg/ml and 2.2 times higher than that of basal media group.
Initial growth rate of granulosa cells in FSH-treated group was much faster than that of basal media group, but the growth rate from 24 to 72 hours of culture was slower in FSH-treated group.
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