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Related to mesonephros: metanephros, mesonephric duct


 (mĕz′ə-nĕf′rəs, -rŏs′, mĕs′-)
The second of the three excretory organs that develop in a vertebrate embryo, becoming the functioning kidney in fish and amphibians but replaced by the metanephros in birds, reptiles, and mammals. Also called Wolffian body.

[meso- + Greek nephros, kidney.]

mes′o·neph′ric adj.


(Zoology) the middle part of the embryonic kidney in vertebrates, becoming the adult kidney in fishes and amphibians and the epididymis in reptiles, birds, and mammals. See also pronephros, metanephros
[C19: New Latin, from meso- + Greek nephros kidney]
ˌmesoˈnephric adj


(ˌmɛz əˈnɛf rɒs, ˌmɛs-, ˌmi zə-, -sə-)

n., pl. -roi (-roi).
an excretory organ of vertebrate embryos, developing into the functional kidney in fishes and amphibians and into part of the ducts and tubules of the reproductive system in reptiles, birds, and mammals.
[1875–80; meso- + Greek nephrós kidney]
mes`o•neph′ric, adj.
References in periodicals archive ?
The role of the mesonephros in cell differentiation and morphogenesis of the mouse fetal testis.
mesenchymal fibroblasts from the mesonephros and mesenchymal fibroblasts from the gonadal ridge (Byskov, 1986; Buehr and McLaren, 1992; De Kretser and Kerr, 1994; Merchant-Larios et al.
The embryonic kidney develops through three stages: the pronephros, the mesonephros, which both will regress throughout development, and the metanephros, which forms the final kidney.
Embryonic mesonephros is supplied by about 30 lateral branches, which develop as segmental arteries from dorsal aorta extending from C6 to L3 segment forming a network called rete arteriosum urogenitale.
It is suggested that regression of mesonephros, deceleration in the growth rate of the liver, and the enlargement of the abdominal cavity might be the triggering factors of the the intestinal return (3-9).
sup][8] According to him, the developing mesonephros, metanephros, and gonads are supplied by nine pairs of lateral mesonephric arteries arising from the dorsal aorta.
One theory for the development of SNT is that there is incomplete degeneration of a portion of the mesonephros and subsequent development of peritoneal bands [3].
Like the mesonephros, the skeletal system is also derived from the mesoderm, at approximately the same stage of development and at the same somite levels which are involved for the embryonic development of urogenital tract, which explains the skeletal abnormalities.
Conclusion: The proximal tubular and luminal diameters and epithelial height of the cells lining the proximal tubules of mesonephros were affected by not only advancement in the mobile phones but also increase in the exposure time to the radiations.
longitudinal division of the urogenital ridge, incomplete degeneration of a part of the mesonephros and development of peritoneal bands have been suggested, but none can explain all types of polyorchidism.
22-25) Deletion of both PAX8 and PAX2 genes prevents generation of the mesonephric (wolffian) duct and subsequent formation of all three embryonic kidneys (pronephros, mesonephros, and metanephros).
Left and right gonads were visualized using a Nikon SMZ-U dissecting microscope (Nikon Instruments, Melville, NY), separated from adjacent mesonephros, and transferred to individual labeled wells of ice-cold transport media until xenografting.