müllerian duct

(redirected from Paramesonephric ducts)
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duct

 [dukt]
a passage with well-defined walls, especially a tubular structure for the passage of excretions or secretions. adj., adj ductal.
accessory duct of Santorini a tubular structure that drains the lower part of the head of the pancreas.
alveolar d's small passages connecting the respiratory bronchioles and the alveolar sacs.
Bartholin's duct (duct of Bartholin) the larger and longer of the sublingual ducts.
bile d's (biliary d's) see bile ducts.
cochlear duct a spiral membranous tube in the bony canal of the cochlea between Reissner's membrane and the basilar membrane; it is divided into the scala tympani, scala vestibuli, and spiral lamina. Called also scala media.
common bile duct a duct formed by the union of the cystic and hepatic ducts; see also bile ducts.
cystic duct the passage connecting the gallbladder neck and the common bile duct.
efferent duct any duct that gives outlet to a glandular secretion.
ejaculatory duct the duct formed by union of the ductus deferens and the duct of the seminal vesicles, opening into the prostatic urethra on the colliculus seminalis.
endolymphatic duct a canal connecting the membranous labyrinth of the ear with the endolymphatic sac.
excretory duct one through which the secretion is conveyed from a gland.
hepatic duct the excretory duct of the liver, or one of its branches in the lobes of the liver; see also bile ducts.
Hepatic duct. From Applegate, 2000.
lacrimal duct the excretory duct of the lacrimal gland; see also lacrimal apparatus. Called also lacrimal canaliculus.
lacrimonasal duct nasal duct.
lactiferous d's ducts conveying the milk secreted by the lobes of the breast to and through the nipples.
lymphatic duct, left thoracic duct.
lymphatic d's see lymphatic ducts.
mammary duct lactiferous ducts.
mesonephric duct an embryonic duct of the mesonephros, which in the male becomes the epididymis, ductus deferens and its ampulla, seminal vesicles, and ejaculatory duct, and in the female is largely obliterated.
müllerian duct either of the two paired embryonic ducts developing into the vagina, uterus, and fallopian tubes, and becoming largely obliterated in the male.
nasal duct (nasolacrimal duct) the downward continuation of the lacrimal sac, opening on the lateral wall of the inferior meatus of the nose; see also lacrimal apparatus.
pancreatic duct the main excretory duct of the pancreas, which usually unites with the common bile duct before entering the duodenum at the major duodenal papilla; see also bile ducts.
papillary d's straight excretory or collecting portions of the renal tubules, which descend through the renal medulla to a renal papilla.
paramesonephric duct müllerian duct.
paraurethral d's Skene's glands.
parotid duct the duct by which the parotid glands empty into the mouth.
prostatic d's minute ducts from the prostate, opening into or near the prostatic sinuses on the posterior wall of the urethra.
lymphatic duct, right a vessel draining lymph from the upper right side of the body, receiving lymph from the right subclavian, jugular, and mediastinal trunks when those vessels do not open independently into the right brachiocephalic vein.
salivary d's the ducts of the salivary glands.
semicircular d's the long ducts of the membranous labyrinth of the ear.
seminal d's the passages for conveyance of spermatozoa and semen.
sublingual d's the excretory ducts of the sublingual salivary glands.
submandibular duct (submaxillary duct) the duct that drains the submandibular gland and opens at the sublingual caruncle.
tear duct lacrimal duct.
thoracic duct a duct beginning in the cisterna chyli and emptying into the venous system at the junction of the left subclavian and left internal jugular veins. It acts as a channel for the collection of lymph from the portions of the body below the diaphragm and from the left side of the body above the diaphragm.

par·a·mes·o·neph·ric duct

either of the two paired embryonic ducts extending along the mesonephros roughly parallel to the mesonephric duct and emptying into the cloaca; in the female, the upper parts of the ducts form the uterine tubes, whereas the lower fuse to form the uterus and part of the vagina; in the male, vestiges of the ducts form the prostatic utricle and the appendix testis.

Müllerian duct

An embryonic structure that, in females, develops into the ducts of the reproductive system. The Müllerian duct degenerates in the male under the influence of the protein Müllerian inhibiting substance. (Johannes Peter Müller, German physiologist and comparative anatomist, 1801–58).

Mullerian duct

the duct from the embryonic PRONEPHROS which in later development in mammals becomes the oviduct in females and disappears in males. It is named after the German anatomist and physiologist Johannes Müller (1801–58).
References in periodicals archive ?
However, Larsen WJ [13] concluded that the paramesonephric ducts arise by craniocaudal invagination of a ribbon of thickened coelomic epithelium.
The uterus is the most important reproductive organ present in the pelvis, a constituent of the internal female reproductive tract which develops from a paired paramesonephric duct, originating from coelomic epithelium extending beside the mesonephric ducts.
At 55 days of age the ovaries of the female fetus are closely associated with the paramesonephric ducts (Figure 4-5b).
Another important difference between the developing ovary and testis is that the paramesonephric duct does not invade the ovary; that is, there is no tubular system connecting the ovary with the paramesonephric duct.
The hypospadias, lack of prostate and redundant vagina would suggest that the testosterone levels were not sufficient to induce full gland development, or full paramesonephric duct degradation.
The cranial part of the paramesonephric ducts forms the uterine tubes, and the coelomic invagination remains as the pelvic opening of the fallopian tube.
In females the mesonephric ducts degenerate and by twelve weeks due to lack of testosterone and the paired paramesonephric developed on lateral aspect of mesonephrons to reach urogenital sinus at nine weeks and unfused lateral arms of paramesonephric ducts forming fallopian tubes.
DISCUSSION: The mullerian or paramesonephric ducts arise as longitudinal invaginations of the coelomic epithelium along the anterolateral surfaces of the nephrogenital ridges in the posterior abdominal wall.
Partial lack of fusion of two paramesonephric ducts produces a single cervix with varying degrees of separation in two uterine horns, leading to bicornuate uterus.
DISCUSSION: Septate uterus considered a type of uterine duplicational anomaly and results from partial or complete failure of resorption of the uterovaginal septum after fusion of the paramesonephric ducts. The septum is usually fibrous but can also have varying muscular components.
DISCUSSION: Unicornuate uterus results from the failure in the development of one of the paramesonephric ducts either partially or completely.
DISCUSSION: The uterus is developed during embryogenesis by the fusion of the two paramesonephric ducts (also called mullerian ducts).The two mullerian ducts fuse into a single uterine body.