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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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(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
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(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.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
Normal embryonic development was also including heart, liver, gut, and mesonephros (Fig.
Pronephros, mesonephros, and metanephros represent the three primitive kidneys, present during the various developmental stages of the human embryo.
According to the most accepted theory, the kidney reaches the adult location at the eighth gestational week followed by the superior accelerated migration of the metanephros and the delay in mesonephros involution before completing the diaphragmatic development, that is, before the fusion of the pleuroperitoneal membrane.
Two sources for the precursors of fetal Leydig cells have been reported in the literature, viz., 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., 1993; Nishino et al., 2001).
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.[sup][5]
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).
The embryologic explanation of these variations has been presented and discussed by Felix.[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.
The adult kidney is a mesonephros. The nephrons consist of a glomerulus in the Bowman's capsule and a renal tubule that is divided into the following morphologically distinguishable segments: a neck segment; proximal tubule; thin, intermediate segment; early distal tubule; late distal tubule; and connecting tubule linked to the collecting duct (Uchiyama and Yoshizawa, 2002; Hillman et al., 2009; Kardong, 2012; Larsen et al., 2014) (Fig.
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.