WordNet

a continuous tube formed by a row of elongated cells lacking intervening end walls
an enclosed conduit for a fluid
a bodily passage or tube lined with epithelial cells and conveying a secretion or other substance; "the tear duct was obstructed"; "the alimentary canal"; "poison is released through a channel in the snakes fangs" (同)epithelial duct, canal, channel

PrepTutorEJDIC

送水管;(建物・船などの)通気管;(地下ケーブルなどの)ダクト / (体液を運ぶ)導管,(植物が水・空気を運ぶ)導管

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2012/08/06 01:01:04」(JST)

wiki en

Mesonephric duct

Urogenital sinus of female human embryo of eight and a half to nine weeks old.

Transverse section of a chick embryo of forty-five hours' incubation.
Latin	ductus mesonephricus; ductus Wolffi
Gray's	subject #252 1205
Carnegie stage	11
Days	28
Precursor	intermediate mesoderm
Gives rise to	vas deferens, seminal vesicles, epididymis
Code	TE E5.6.2.0.0.0.4

The mesonephric duct (also known as Wolffian duct, archinephric duct, Leydig's duct and nephric duct) is a paired organ found in mammals including humans during embryogenesis.

It connects the primitive kidney Wolffian body (or mesonephros) to the cloaca and serves as the anlage for certain male reproductive organs.

Development

Wolffian duct (red) degenerates in females (middle image) and develops in males (bottom).

In both the male and the female the Wolffian duct develops into the trigone of urinary bladder, a part of the bladder wall. However, further development differentiates between the sexes in the development of the urinary and reproductive organs.

Male development

In a male, it develops into a system of connected organs between the efferent ducts of the testis and the prostate, namely the epididymis, the vas deferens, and the seminal vesicle. The prostate forms from the urogenital sinus and the efferent ducts form from the mesonephric tubules.

For this it is critical that the ducts are exposed to testosterone during embryogenesis. Testosterone binds to and activates androgen receptor, affecting intracellular signals and modifying the expression of numerous genes..^[1]

In the mature male, the function of this system is to store and mature sperm, and provide accessory semen fluid.

Female development

In the female, in the absence of testosterone support, the Wolffian duct regresses, and inclusions may persist. The epoophoron and Skene's glands may be present. Also, lateral to the wall of the vagina a Gartner's duct or cyst could develop as a remnant.

The derivatives of the Mesonephric duct can be remembered using the mnemonic, "Gardener's SEED" for Gartner's duct, Seminal vesicles, Epididymis, Ejaculatory duct and Ductus deferens.^[2]

History

It is named after Caspar Friedrich Wolff who described the mesonephros and its ducts in his dissertation in 1759.^[3]

Additional images

Diagram of a transverse section, showing the mode of formation of the amnion in the chick.
Reconstruction of a human embryo of 17 mm.
Cloaca of human embryo from twenty-five to twenty-seven days old.
Broad ligament of adult, showing epoophoron.
Transverse section of human embryo eight and a half to nine weeks old.
Tail end of human embryo twenty-five to twenty-nine days old.
Tail end of human embryo thirty-two to thirty-three days old.
Tail end of human embryo; from eight and a half to nine weeks old.
Primitive kidney and bladder, from a reconstruction.

References

^ Hannema SE, Print CG, Charnock-Jones DS, Coleman N, Hughes IA (2006). "Changes in gene expression during Wolffian duct development". Horm. Res. 65 (4): 200–9. doi:10.1159/000092408. PMID 16567946.
^ "Wolffian duct: Derivatives". LifeHugger. http://mc.lifehugger.com/moc/1232/Vitelline_veins_Derivatives. Retrieved 2009-12-12.
^ synd/2845 at Who Named It?

External links

Mnemonic at medicalmnemonics.com 1266
How the Body Works / Sex Development / Sexual Differentiation / Duct Differentiation - The Hospital for Sick Children (GTA - Toronto, Ontario, Canada)

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 小児における先天性鼻涙管閉塞（涙管閉鎖症）および涙嚢ヘルニア congenital nasolacrimal duct obstruction dacryostenosis and dacryocystocele
2. 総胆管損傷の修復 repair of common bile duct injuries
3. 甲状舌管嚢胞および異所性甲状腺 thyroglossal duct cysts and ectopic thyroid
4. 肝内胆管の消失および胆管消失症候群 hepatic ductopenia and vanishing bile duct syndrome
5. 成人における外傷による十二指腸および膵臓損傷のマネージメント management of duodenal and pancreatic trauma in adults

English Journal

A Gartner Duct Cyst Masquerading as Anterior Vaginal Prolapse.

Davidson ERW1, Barber MD.
Obstetrics and gynecology.Obstet Gynecol.2017 Nov;130(5):1039-1041. doi: 10.1097/AOG.0000000000002315.
PMID 29016495

Unilateral Complete Agenesis of Mesonephric Duct Derivatives in an 82-year-Old Male Cadaver: Embryology, Anatomy and Clinical Considerations.

Darcy DG1, Yao-Cohen M2, Olson TR2, Downie SA2,3.
Urology case reports.Urol Case Rep.2017 Sep 1;15:20-22. doi: 10.1016/j.eucr.2017.06.003. eCollection 2017 Nov.
PMID 28879095

Elimination of the male reproductive tract in the female embryo is promoted by COUP-TFII in mice.

Zhao F1, Franco HL1, Rodriguez KF1, Brown PR1, Tsai MJ2, Tsai SY2, Yao HH3.
Science (New York, N.Y.).Science.2017 Aug 18;357(6352):717-720. doi: 10.1126/science.aai9136.
PMID 28818950

Japanese Journal

Spontaneous Renal Mixed Epithelial and Stromal Tumor (MEST) in a Beagle

YAMAOKA Makiko,SATO Yasukazu,MASUMOTO Yoshihiro,ENOMOTO Makoto,MITSUMORI Kunitoshi
Journal of toxicologic pathology 21(3), 189-192, 2008-09-30
… Morphologically, these proliferative ductal structures were suggestive of a primitive duct arising from the mesonephric or paramesonephric tubule. …
NAID 10027894549

対側停留精巣と同側腎無形成を伴った中腎管遺残の1例

井上貴昭,六車光英,福井勝也 [他]
泌尿器科紀要 54(4), 309-312, 2008-04
30歳男性。患者は不妊症を主訴に近医を受診, 無精子症を指摘され, 著者らの施設へ紹介受診となった。妻には産婦人科的な異常を認めず, 精査の結果, 骨盤内精管欠損による閉塞性無精子症を疑い, 手術が行われた。術中所見では右側の停留精巣および腎無形成を伴った中腎管遺残が確認され, crossed vasovasostomyは困難と判断し, 手術を終了した。その後, 文献的に考察し, 右は停留精巣によ …
NAID 120001178034