Disputed Talk FolliculogenesisFolliculogenesis in adult individuals March 2012 date March 2012 Image ... luteum In biology , folliculogenesis is the maturation of the ovarian follicle , a densely packed shell of somatic cells that contains an immature oocyte . Folliculogenesis describes the progression of a number of small Folliculogenesis Primordial primordial follicles into large Folliculogenesis ..., folliculogenesis ends when the remaining follicles in the Ovary ovaries are incapable of responding ..., this article will deal exclusively with human folliculogenesis. Overview The primary role of the follicle ..., Folliculogenesis Primordial primordial follicles . These follicles each contain a similarly immature ... begins folliculogenesis, entering a growth pattern that will end in death or in ovulation the process ..., the follicles have transitioned to Folliculogenesis Primordial tertiary, or antral, follicles ... until only one follicle is left. This remaining follicle, Folliculogenesis Late tertiary and preovulatory ... , ruptures and discharges the oocyte that has since grown into a secondary oocyte , ending folliculogenesis. Image Folliculogenesis chart.gif frame center Diagram of folliculogenesis, starting from pre antral late secondary , courtesy NCBI Phases of development Folliculogenesis lasts for approximately ... unfamiliar terms will be defined in their respective sections In a larger perspective, the whole folliculogenesis ... range from 25,000 to 1.5 million . ref name WKmodel By virtue of the inefficient nature of folliculogenesis ... amounts of progesterone and minor amounts of estrogen . These two steps, while not part of folliculogenesis ... topics be reviewed. Hormone function As with most things related to the reproductive system, folliculogenesis ... of positive and negative feedback to regulate folliculogenesis. They are gonadotropin releasing ... thirteen LH spikes during the course of normal folliculogenesis. However, coordinated enzyme signalling ... for folliculogenesis, and they steadily decline until menopause . See also ovarian follicle granulosa ... more details
Infobox Anatomy Name Follicular antrum Latin antrum follicularum GraySubject GrayPage Image Caption Mature late stage tertiary Graffian follicle. Image2 Caption2 Early folliculogenesis from primordial to early tertiary. Precursor System Artery Vein Nerve Lymph MeshName MeshNumber DorlandsPre a 50 DorlandsSuf 12143527 The follicular antrum is the portion of an ovarian follicle filled with liquor folliculi . See also antrum External links KansasHistology female female07 Graafian Follicle UCDavisOrganology Reproductive mammal ovary2 ovary2 Mammal, canine ovary LM, High http www.cvm.okstate.edu instruction mm curr histology fr HiFRp09.htm Description at okstate.edu Female reproductive system DEFAULTSORT Follicular Antrum Category Female reproductive system genitourinary stub it Antro follicolare pl Jama p cherzyka jajnikowego ... more details
An antral follicle or Graafian follicle is an ovarian follicle during a certain latter stage of folliculogenesis . Definitions differ in where the shift into an antral follicle occurs in the staging of folliculogenesis, with some stating that it occurs when entering the secondary stage, ref name Lauralee2010 http books.google.com books?id gOmpysGBC90C&pg PT797 Page 769 , section formation of the antrum in Cite book last1 Sherwood first1 Lauralee. last2 first2 title Human physiology from cells to system year 2010 publisher Brooks Cole location Australia United States isbn 9780495391845 pages ref and others stating that it occurs when entering the tertiary stage. ref name Hurk1997 Page 76 in cite doi 10.1016 S0093 691X 96 00341 X ref Appearance It is marked by the formation of a fluid filled cavity adjacent to the oocyte called the Follicular antrum antrum . The basic structure of the mature follicle has formed and no novel cells are detectable. Granulosa and theca cells continue to undergo mitosis concomitant with an increase in antrum volume. Antral follicles can attain a tremendous size that is hampered only by the availability of follicle stimulating hormone FSH , which it is dependent on in this stage of folliculogenesis. By command of an oocyte secreted morphogenic gradient, the antral follicle s granulosa cells begin to differentiate themselves into four distinct subtypes corona radiata that surrounds the zona pellucida , membrana that s interior to the basal lamina, periantral that s adjacent to the antrum, and cumulus oophorous that connects the membrana and corona radiata granulosa cells together. Each type of cell behaves differently in response to FSH. Endocrine properties Theca cells express receptors for luteinizing hormone LH . LH kicks off the production of androgen s by the theca cells, most notably androstendione , which are aromatized by granulosa cells to produce estrogens , primarily estradiol . Consequently, estrogen levels begin to rise. Antral follicle ... more details
Infobox Anatomy Name Theca of follicle Latin theca folliculi GraySubject GrayPage Image Caption Mature late stage tertiary Graffian follicle Image2 Caption2 Early folliculogenesis from primordial to early tertiary. Precursor System Artery Vein Nerve Lymph MeshName MeshNumber DorlandsPre t 07 DorlandsSuf 12801620 The theca folliculi comprise a layer of the ovarian follicle s. They appear as the follicles become tertiary follicle s. The theca are divided into two layers, the theca interna and the theca externa . The theca interna is responsible for the production of androstenedione , and indirectly the production of 17 estradiol , also called E2, by supplying the neighboring granulosa cells with androstenedione that with the help of the enzyme aromatase can be used as a substrate for this type of estradiol . See also theca thecoma External links BUHistology 14805loa UCDavisOrganology Reproductive mammal ovary2 ovary5 Mammal, canine ovary LM, High UCDavisOrganology Reproductive mammal ovary5 ovary6 Mammal, bovine ovary LM, Medium UIUCHistologySubject 372 interna UIUCHistologySubject 373 externa AnatomyAtlasesMicroscopic 13 249 http www.trinity.edu rblyston MicroA Lectures L39 html sld016.htm Slide at trinity.edu Female reproductive system DEFAULTSORT Theca Of Follicle Category Female reproductive system genitourinary stub it Teca follicolare ... more details
PBB geneid 344018 Folliculogenesis specific basic helix loop helix , also known as factor in the germline alpha FIGalpha or transcription factor FIGa , is a protein that in humans is encoded by the FIGLA gene . ref name entrez cite web title Entrez Gene folliculogenesis specific basic helix loop helix url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 344018 accessdate ref ref name pmid12468641 cite journal author Huntriss J, Gosden R, Hinkins M, Oliver B, Miller D, Rutherford AJ, Picton HM title Isolation, characterization and expression of the human Factor In the Germline alpha FIGLA gene in ovarian follicles and oocytes journal Mol. Hum. Reprod. volume 8 issue 12 pages 1087 95 year 2002 month December pmid 12468641 doi 10.1093 molehr 8.12.1087 url issn ref Function This gene encodes a protein that functions in postnatal oocyte specific gene expression. The protein is a basic helix loop helix transcription factor that regulates multiple oocyte specific genes, including genes involved in folliculogenesis and those that encode the zona pellucida . ref name entrez Clinical significance Mutation in the FIGLA gene are associated with premature ovarian failure . ref name pmid18499083 cite journal author Zhao H, Chen ZJ, Qin Y, et al. title Transcription factor FIGLA is mutated in patients with premature ovarian failure journal Am. J. Hum. Genet. volume 82 issue 6 pages 1342 8 year 2008 month June pmid 18499083 pmc 2427265 doi 10.1016 j.ajhg.2008.04.018 url ref References reflist Further reading refbegin 2 cite journal author Miyamoto T, Sengoku K, Takuma N, et al. title Isolation and expression analysis of the testis specific gene, STRA8, stimulated by retinoic acid gene 8. journal J. Assist. Reprod. Genet. volume 19 issue 11 pages 531 5 year 2002 pmid 12489526 doi cite journal author Suzumori N, Pangas SA, Rajkovic A title Candidate genes for premature ovarian failure. journal Curr. Med. Chem. volume 14 issue 3 pages 353 7 year 2007 pmid ... more details
human begins with the processes of folliculogenesis , oocytogenesis , and ootidogenesis . Human ... II has completed, an ootid and another polar body have now been created. Folliculogenesis Main Folliculogenesis ... more details
Folliculogenesis Primordial follicles are indiscernible to the naked eye. However, these eventually ... perspective, the whole folliculogenesis from primordial to preovulatory follicle is located in the stage ... more details
of the preovulatory follicle Main Folliculogenesis Through a process that takes approximately 375 days ... cycle, suggesting that the endocrine system does not regulate folliculogenesis stringently. Researchers ... and engage in negative feedback of folliculogenesis and ovulation. Animals linked to Painted turtle ... fertilization. See also Anovulatory cycle Corpus luteum Folliculogenesis Menstrual cycle Oogenesis ... more details
Deleted image removed Image mature Graffian follicle.jpg frame right Histology of the preovulatory follicle A granulosa cell or follicular cell is a somatic cell of the sex cord that is closely associated with the developing female gamete called an oocyte or egg in the ovary of mammal s. Anatomy and function In the primary ovarian follicle , and later in follicle development folliculogenesis , granulosa cells advance to form a multilayered cumulus oophorus surrounding the oocyte in the preovulatory or Graafian follicle . The major functions of granulosa cells include the production of sex steroid s, as well as myriad growth factors thought to interact with the oocyte during its development. The sex steroid production consists of follicle stimulating hormone FSH stimulating granulosa cells to convert androgens coming from the thecal cell s to estradiol by aromatase during the follicular phase of the menstrual cycle . ref cite pmid 6422764 ref However, after ovulation the granulosa cells turn into granulosa lutein cell s that produce progesterone . The progesterone may maintain a potential pregnancy and causes production of a thick cervical mucus that inhibits sperm entry into the uterus. Embryology of ovarian granulosa cells In the development of the urinary and reproductive organs , the oogonia become invaginated in the gonadal ridge . In the 1970 s, evidence emerged that the first cells to make contact with the oogonia were of mesonephric origin. It was suggested that mesonephric cells already closely associated with the oogonia proliferated throughout development to form the granulosa cell layer. ref cite journal author Satoh M title Histogenesis and organogenesis of the gonad in human embryos journal J Anat volume 177 issue pages 85 107 year 1991 pmid 1769902 pmc 1260417 ref ref cite journal author Upadhyay S, Zamboni L title Preliminary observations on the role of the mesonephros in the development of the adrenal cortex journal Anat Rec volume 202 issue 1 pages ... more details
cleanup date October 2010 Infobox Anatomy Name Immature ovum Latin GraySubject GrayPage Image Caption Image2 Caption2 System MeshName MeshNumber An immature ovum is a cell that goes through the process of oogenesis to become an ovum . It can be an oogonium , an oocyte or an ootid . An oocyte, in turn, can be either primary or secondary, depending on how far it has come in its process of meiosis . class wikitable Cell type ploidy chromosomes chromatids Process Process completion Oogonium diploid 46 2N Oocytogenesis mitosis third trimester primary Oocyte diploid 46 4N Ootidogenesis meiosis 1 Folliculogenesis polar body separated Dictyate in prophase I until ovulation secondary Oocyte haploid 23 2N Ootidogenesis meiosis 2 polar body separated Halted in metaphase II until fertilization Ootid haploid 23 1N Maturation Minutes after fertilization Ovum haploid 23 1N Oogonium Main Oogonium Oogonia are the cells that turn into primary oocytes in oogenesis. ref http www.answers.com topic oogonium?cat health answers.com ref They are diploid, i.e. containing both pairs of homologous chromosomes. There are 23 chromosome pairs. Thus there are 46 chromosomes. Each chromosome, however, hasn t yet duplicated itself. Thus, there are only one chromatid on each chromosome, making the total quantity of chromatids 46. This is twice the number of chromosome pairs 2N . Timeline Oogonia are created in early embryo nic life. All have turned into primary oocytes at late fetal age. Primary oocyte Main Oocyte The primary oocyte is defined by its process of ootidogenesis , which is meiosis. ref http www.biochem.northwestern.edu holmgren Glossary Definitions Def P primary oocyte.html Biochem ref It has duplicated its DNA, so that each chromosome has two chromatids, i.e. 92 chromatids all in all 4C . When meiosis I is completed, one secondary oocyte and one polar body is created. Timeline Primary oocytes have been created in late fetal life. This is the stage where immature ova spend most of their ... more details
cite journal author Grier HJ, Uribe MC, Parenti LR title Germinal epithelium, folliculogenesis, and postovulatory ...&ndash 824 See also Folliculogenesis polar body External links http it.stlawu.edu mtem devbiol atlas ... more details
folliculogenesis. journal Nature volume 383 issue 6600 pages 531 5 year 1996 pmid 8849725 doi 10.1038 ... factor 9 GDF 9 and its novel homolog GDF 9B are expressed in oocytes during early folliculogenesis ... more details
About lymph primary follicles ovarian primary follicles Folliculogenesis Infobox Anatomy Name PAGENAME Latin GraySubject 175 GrayPage 689 Image germinal center.svg Caption Germinal center of a lymph node showing proliferation and development stages of a B cell . Image2 Caption2 Precursor System Artery Vein Nerve Lymph MeshName MeshNumber DorlandsPre c 20 DorlandsSuf 12226657 Germinal centers or germinal centres GC are sites within lymph nodes also within lymph nodules in peripheral lymph tissues where mature B lymphocytes rapidly proliferate, differentiate, mutate their antibodies through somatic hypermutation , and immunoglobulin class switching class switch their antibodies during a normal immune response to an infection. During this process of rapid division and selection, B cells are known as centroblasts, and once they have stopped proliferating they are known as centrocyte centrocytes . Germinal centers are an important part of the B cell humoral immunity humoral immune response . They develop dynamically after the activation of B cell s by T dependent antigen . Histology Histologically , the GCs describe microscopically distinguishable parts in lymphoid tissues. Process 1. Activated B cells migrate from the primary focus of infection into the primary lymph follicle follicles and begin monoclonal expansion in the environment of follicular dendritic cell s FDC . During this time they are referred to as centroblasts. 2. After several days of expansion the B cells undergo somatic hypermutation , a process by which they mutate their antibody encode encoding DNA and thus generate a diversity of Clone genetics clone s in the germinal center. This involves pseudo random substitutions biased towards regions encoding the antigen recognition surface of the antibodies the B cells produce. During this time they also undergo isotype switching, or class switching. 3. Upon some unidentified stimulus from the FDC, the maturing B cells centroblasts migrate from the dark zone to the light ... more details
File MenstrualCycle2 en.svg thumb 350px right Menstrual cycle The follicular phase or proliferative phase is the phase of the estrous cycle , or, in humans and great ape s, the menstrual cycle during which follicles in the ovary mature. It ends with ovulation . The main hormone controlling this stage is estradiol . ref cite paper author Bagnell, C title Animal Reproduction publisher Rutgers University Department of Animal Sciences year 2005 ref Hormonal events Follicle recruitment Follicle stimulating hormone FSH is secreted by the anterior pituitary gland . FSH secretion begins to rise in the last few days of the previous menstrual cycle, ref name tcoyf cite book first Toni last Weschler year 2002 title Taking Charge of Your Fertility pages 359 361 edition Revised publisher HarperCollins location New York isbn 0 06 093764 5 ref and is highest and most important during the first week of the follicular phase. ref name silverthorn cite book author Dee Unglaub Silverthorn title Human physiology an integrated approach publisher Pearson Benjamin Cummings location San Francisco year 2004 isbn 0 13 102015 3 edition Third pages Chapter 26 Reproduction and Development, and Chapter 23 Endocrine control of growth and metabolism nopp true ref The rise in FSH levels recruits five to seven tertiary stage ovarian follicle s this stage follicle is also known as a Graafian follicle or Follicular antrum antral follicle for entry into the menstrual cycle. These follicles, that have been growing for the better part of a year in a process known as folliculogenesis , compete with each other for dominance. FSH induces the proliferation of granulosa cell s in the developing follicles, and the expression of luteinizing hormone LH receptors on these granulosa cells. Under the influence of FSH, aromatase and p450 enzymes are activated, causing the granulosa cells to begin to secrete estrogen . This increased level of estrogen stimulates production of gonadotropin releasing hormone GnRH , whic ... more details
PBB geneid 9210 Bone morphogenetic protein 15 is a protein that in humans is encoded by the BMP15 gene . ref name pmid9849956 cite journal author Dube JL, Wang P, Elvin J, Lyons KM, Celeste AJ, Matzuk MM title The bone morphogenetic protein 15 gene is X linked and expressed in oocytes journal Mol Endocrinol volume 12 issue 12 pages 1809 17 year 1999 month Feb pmid 9849956 pmc doi 10.1210 me.12.12.1809 ref ref name entrez cite web title Entrez Gene BMP15 bone morphogenetic protein 15 url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 9210 accessdate ref The protein encoded by this gene is a member of the transforming growth factor beta TGF superfamily. It is a paracrine signaling molecule involved in oocyte and ovarian follicle follicular development. Using Northern blot analysis, BMP15 has been shown to be exclusively expressed in the ovaries . It is thought that this protein may be involved in oocyte maturation and follicular development as a homodimer or by forming heterodimer s with a related protein, Growth differentiation factor 9 Gdf9 . ref name entrez References reflist Further reading refbegin 2 PBB Further reading citations cite journal author Aaltonen J, Laitinen MP, Vuojolainen K, et al. title Human growth differentiation factor 9 GDF 9 and its novel homolog GDF 9B are expressed in oocytes during early folliculogenesis. journal J. Clin. Endocrinol. Metab. volume 84 issue 8 pages 2744 50 year 1999 pmid 10443672 doi 10.1210 jc.84.8.2744 cite journal author Galloway SM, McNatty KP, Cambridge LM, et al. title Mutations in an oocyte derived growth factor gene BMP15 cause increased ovulation rate and infertility in a dosage sensitive manner. journal Nat. Genet. volume 25 issue 3 pages 279 83 year 2000 pmid 10888873 doi 10.1038 77033 cite journal author Otsuka F, Yao Z, Lee T, et al. title Bone morphogenetic protein 15. Identification of target cells and biological functions. journal J. Biol. Chem. volume 275 issue 50 pages 3952 ... more details
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