|Budget Amount *help
¥5,900,000 (Direct Cost : ¥5,900,000)
Fiscal Year 1993 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1992 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Fiscal Year 1991 : ¥3,700,000 (Direct Cost : ¥3,700,000)
1) Polar body formation inhibitory protein : A protein, which inhibits polar body formation, was purified from a urine preparation from pregnant women. Amino terminal sequence analysis showed that residues 5 to 15 of this protein were identical to the residues 1 to 11 of human nonsecretory ribonuclease. Furthermore, residues 1 to 4 of this protein were identical to residues -4 to -1, corresponding to part of a single peptide region of eosinophil-derived neurotoxin, whose mature sequence is identical to nonsecretory ribonuclease.
2) Glycosaminoglycans promoting viability of oocytes : OOcytes situated within the atretic follicles will undergo degeneration by segmentation, forming several to many "blastomeres" containing none to multiple nuclear fragments. A similar type of segmentation was observed in degenerating oocytes cultured in vitro. The observation that segmentation occurred more often with cumulus-free oocytes suggests that cumulus cells may produce a component(s) that would dela
y the degenerative process. Glycosaminoglycans(GAGs) isolated from bovine follicular fluid(bFF) and added to the suspending medium prevented the occurrence of spontaneous segmentation in isolated cumulus-free mouse oocytes in a dose-dependent manner. To identify the active factor, specific GAG was purified from bFF.The fraction with a retention time nearly coincident with that of hyaluronic acid prevented the occurrence of segmentation.
4) Ovarian angiogenesis and maturation of oocytes/follicles : In the ovary, there is a striking difference in the distribution of blood vessels to individual follicles. Epidermal growth factor (EGF), which induces capillary proliferation in vivo, was identified in granulosa, thecal and interstitial cells, suggesting that EGF is involved in neovascularization of the ovary. However, angiogenesis in the ovary is observed in specific regions of the follicles, especially the thecal layr. Thus it is surmized that ovarian components modulate the activity of ovarian EGF.We observed that GAGs isolated from mouse ovaries were potent enhancers of the activity of EGF by interacting or complexing with it.