Urogenital sinus
{{Short description|Embryological part during the development of the urinary and reproductive organs in mammals}}
{{Infobox embryology
| Name = Urogenital sinus
| Latin = sinus urogenitalis definitivus
| Image = Gray1109.png
| Caption = Urogenital sinus of female human embryo of eight and a half to nine weeks old. (Urogenital sinus labeled at bottom.)
| Image2 = Development of external sexual organs in the male and female Gray1119.png
| Caption2 = Stages in the development of the external sexual organs in the male and female. ("Opening of urogenital sinus" labeled in diagram D.)
| System =
| CarnegieStage = 15
| Days =
| Precursor = Cloaca
| GivesRiseTo = Urethra, bladder, vagina, vulval vestibule, Bartholin's glands, Skene's glands, prostate, bulbourethral glands
}}
The urogenital sinus is a body part of a human or other placental only present in the development of the urinary and reproductive organs. It is the ventral part of the cloaca, formed after the cloaca separates from the anal canal during the fourth to seventh weeks of development.{{sfn |Sadler |Langman |2010 |pp=243–244}}
In males, the UG sinus is divided into three regions: upper, pelvic, and phallic. The upper part gives rise to the urinary bladder and the pelvic part gives rise to the prostatic and membranous parts of the urethra,{{sfn |Sadler |Langman |2010 |pp=243–244}} the prostate and the bulbourethral glands (Cowper's). The phallic portion gives rise to the spongy (bulbar) part of the urethra and the urethral glands (Littré's).
In females, the pelvic part of the UG sinus gives rise to the sinovaginal bulbs, structures that will eventually form the inferior two thirds of the vagina. This process begins when the lower tip of the paramesonephric ducts, the structures that will eventually form the uterus and vaginal fornices, come in contact with the UG sinus. Shortly afterwards, the sinovaginal bulbs form as two solid evaginations of the UG sinus. Cells in these bulbs divide to form a solid vaginal plate, which extends and then canalizes (hollows) to form the inferior portion of the vagina.{{sfn |Sadler |Langman |2010 |pp=253}} The female urogenital sinus also gives rise to the urethra, vestibule, Skene's glands and Bartholin's glands.
Clinical significance
A urogenital sinus anomaly is also a rare birth defect in women where the urethra and vagina both open into a common channel.{{cite book |last=Callahan |first=Gerald N. |title=Between XX and XY : intersexuality and the myth of two sexes |publisher=Chicago Review Press |publication-place=Chicago, Ill. |year=2009 |isbn=978-1-56976-289-9 |oclc=436089205 |page=182}}{{cite web |title=Urogenital Sinus |website=Children's Hospital of Orange County |date=2023-02-23 |url=https://www.choc.org/programs-services/urology/urogenital-sinus/ |access-date=2023-10-07}}
A persistent cloaca is a disorder where the rectum, vagina, and urinary tract meet and fuse, creating a cloaca, a single common channel.{{Citation |author=Jenkins D |title=Mutational analyses of UPIIIA, SHH, EFNB2 and HNF1β in persistent cloaca and associated kidney malformations |journal=J Pediatr Urol |volume=3 |issue=1 |pages=2–9 |year=2007 |pmid=17476318 |doi=10.1016/j.jpurol.2006.03.002 |pmc=1864944 |postscript=. |name-list-style=vanc|author2=Bitner-Glindzicz M |author3=Thomasson L |display-authors=3 |last4=Malcolm |first4=S |last5=Warne |first5=S |last6=Feather |first6=S |last7=Flanagan |first7=S |last8=Ellard |first8=S |last9=Bingham |first9=C}}
Other animals
In many mammals (excluding homonids and some rodents), the urogenital sinus refers to the sinus in which the openings to the female's urethra and vagina are found.{{Cite book |last1=Schatten |first1=Heide |url=https://books.google.com/books?id=B6UsEAAAQBAJ&dq=urogenital+sinus&pg=PA3 |title=Comparative Reproductive Biology |last2=Constantinescu |first2=Gheorghe M. |date=2007-08-14 |publisher=John Wiley & Sons |isbn=978-0-8138-1554-1 |language=en}}{{Cite book |last1=Armati |first1=Patricia J. |url=https://books.google.com/books?id=x3S5v971Nk0C&pg=PA91 |title=Marsupials |last2=Dickman |first2=Chris R. |last3=Hume |first3=Ian D. |date=2006-08-17 |publisher=Cambridge University Press |isbn=978-1-139-45742-2 |language=en}}{{Cite book |last=Grant |first=Tom |url=https://books.google.com/books?id=FASJWgDhxIsC&pg=PA36 |title=The Platypus: A Unique Mammal |date=1995 |publisher=UNSW Press |isbn=978-0-86840-143-0 |language=en}}{{Cite book |last1=Tyndale-Biscoe |first1=C. Hugh |url=https://books.google.com/books?id=HpjovN0vXW4C&pg=PA172 |title=Reproductive Physiology of Marsupials |last2=Renfree |first2=Marilyn |date=1987-01-30 |publisher=Cambridge University Press |isbn=978-0-521-33792-2 |language=en}} However, this term may also apply to some male mammals.
Additional images
File:Gray1107.png|Enlarged view from the front of the left Wolffian body before the establishment of the distinction of sex.
See also
References
{{Reflist}}
=Sources=
- {{cite book |last1=Sadler |first1=T. W. |last2=Langman |first2=Jan |title=Langman's Medical Embryology |publisher=Lippincott William & Wilkins |publication-place=Philadelphia |year=2010 |isbn=978-0-7817-9485-5 |oclc=1194422650}}
External links
- {{cite web |title=Pediatric Conditions - Abnormalities - Vaginal Anomalies: Urogenital Sinus |website=UrologyHealth.org |date=2003-04-29 |url=http://www.urologyhealth.org/pediatric/index.cfm?cat=01&topic=152 |archive-url=https://web.archive.org/web/20040218180228/http://www.urologyhealth.org/pediatric/index.cfm?cat=01&topic=152 |archive-date=2004-02-18 |url-status=dead |ref=none}}
- {{cite web |title=Fetal Pig Dissection |website=Medicine LibreTexts |date=2020-10-15 |url=https://med.libretexts.org/Courses/Kapi%27olani_Community_College/Book%3A_Anatomy_and_Physiology_II_Laboratory_Manual_(Shook)/01%3A_Labs/1.11%3A_Fetal_Pig_Dissection |ref=none |access-date=2023-10-08}}
- {{cite web |title=Development of the reproductive system |website=Amboss.com |date=2022-03-30 |url=https://www.amboss.com/us/knowledge/development-of-the-reproductive-system |ref=none}}
- {{cite web |title=Differentiation of the urogenital sinus in males |website=embryology.ch |date=2007-09-27 |url=http://www.embryology.ch/anglais/ugenital/genitinterne04.html |archive-url=https://web.archive.org/web/20180215193727/http://www.embryology.ch/anglais/ugenital/genitinterne04.html |archive-date=2018-02-15 |url-status=dead |ref=none}}
{{Development of urinary and reproductive systems}}
{{Authority control}}
{{DEFAULTSORT:Urogenital Sinus}}