Talk:Ovary Development: Difference between revisions

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:"'''Follicular atresia''' - Atresia of primary follicles is common during the reproductive period of human females [51]. Our observations suggest that it is a rapid process, assisted by the massive influx of macrophages. The process resembles immune-system mediated corpus luteum regression [94]. Gougeon suggested that depletion of the primary follicle pool is caused mainly by atresia in younger women and by entrance into the growing pool in older women, with the change-over at 38 ± 2.4 years [54]. Since cyclic ovarian function continues in "early premenopausal" women, we speculate that ~10000 primary follicles detected during the age period 40–44 years (Fig. 15B) is a sufficient depot for continuation of ovulatory ovarian function. A 50000 difference compared to younger females fits well with the observation that 70–95% of oocytes in primary follicles show various stages of degeneration [51,52]. It appears that Gougeon was right, and it is possible to conclude that the pool of healthy primary follicles is at least 10000 during the reproductive years."
:"'''Follicular atresia''' - Atresia of primary follicles is common during the reproductive period of human females [51]. Our observations suggest that it is a rapid process, assisted by the massive influx of macrophages. The process resembles immune-system mediated corpus luteum regression [94]. Gougeon suggested that depletion of the primary follicle pool is caused mainly by atresia in younger women and by entrance into the growing pool in older women, with the change-over at 38 ± 2.4 years [54]. Since cyclic ovarian function continues in "early premenopausal" women, we speculate that ~10000 primary follicles detected during the age period 40–44 years (Fig. 15B) is a sufficient depot for continuation of ovulatory ovarian function. A 50000 difference compared to younger females fits well with the observation that 70–95% of oocytes in primary follicles show various stages of degeneration [51,52]. It appears that Gougeon was right, and it is possible to conclude that the pool of healthy primary follicles is at least 10000 during the reproductive years."
:"In adult mammalian ovaries, 70–95% of oocytes are in various stages of degeneration [51,52].
51. Ingram DL: Atresia. In The Ovary (Edited by: Zuckerman S). London: Academic Press 1962, 247-273. 
52. Erickson BH: Development and senescence of the postnatal bovine ovary. J Anim Sci 1966, 25:800-805. PubMed Abstract

Revision as of 03:02, 18 April 2010

  • Aging of the human ovary and testis. Perheentupa A, Huhtaniemi I. Mol Cell Endocrinol. 2009 Feb 5;299(1):2-13. Epub 2008 Nov 18. Review. PMID: 19059459 |


  • Origin of germ cells and formation of new primary follicles in adult human ovaries. Bukovsky A, Caudle MR, Svetlikova M, Upadhyaya NB. Reprod Biol Endocrinol. 2004 Apr 28;2:20. PMID: 15115550 | Reprod Biol Endocrinol.
" During follicle formation, extensions of granulosa cells enter the oocyte cytoplasm, forming a single paranuclear CK+ Balbiani body supplying all the mitochondria of the oocyte. In the ovarian medulla, occasional vessels show an accumulation of ZP+ oocytes (25-30 microns) or their remnants, suggesting that some oocytes degenerate. In contrast to males, adult human female gonads do not preserve germline type stem cells. This study expands our previous observations on the formation of germ cells in adult human ovaries. Differentiation of primitive granulosa and germ cells from the bipotent mesenchymal cell precursors of TA in adult human ovaries represents a most sophisticated adaptive mechanism created during the evolution of female reproduction. Our data indicate that the pool of primary follicles in adult human ovaries does not represent a static but a dynamic population of differentiating and regressing structures. An essential mission of such follicular turnover might be elimination of spontaneous or environmentally induced genetic alterations of oocytes in resting primary follicles."
"Follicular atresia - Atresia of primary follicles is common during the reproductive period of human females [51]. Our observations suggest that it is a rapid process, assisted by the massive influx of macrophages. The process resembles immune-system mediated corpus luteum regression [94]. Gougeon suggested that depletion of the primary follicle pool is caused mainly by atresia in younger women and by entrance into the growing pool in older women, with the change-over at 38 ± 2.4 years [54]. Since cyclic ovarian function continues in "early premenopausal" women, we speculate that ~10000 primary follicles detected during the age period 40–44 years (Fig. 15B) is a sufficient depot for continuation of ovulatory ovarian function. A 50000 difference compared to younger females fits well with the observation that 70–95% of oocytes in primary follicles show various stages of degeneration [51,52]. It appears that Gougeon was right, and it is possible to conclude that the pool of healthy primary follicles is at least 10000 during the reproductive years."
"In adult mammalian ovaries, 70–95% of oocytes are in various stages of degeneration [51,52].

51. Ingram DL: Atresia. In The Ovary (Edited by: Zuckerman S). London: Academic Press 1962, 247-273.

52. Erickson BH: Development and senescence of the postnatal bovine ovary. J Anim Sci 1966, 25:800-805. PubMed Abstract