Opisthonephros

The opisthonephros is the functional adult kidney in lampreys (cyclostomes), most fishes, and amphibians.^[1] It is formed from the extended mesonephros along with tubules from the posterior nephric ridge.^[2] The functional embryonic kidney in anamniotes is the pronephros.

Kerr coined the term ‘opisthonephros’ in 1919.^[3] In 1949, Hyman wrote the opisthonephros “has used up the mesomere tissue from which in amniotes both mesonephros and metanephros come.”^[3] Some accounts call opisthonephros the ‘mesonephros’, but the opisthonephros in anamniotes (lampreys, fish, and amphibians) differ considerably than the mesonephros in amniotes (reptiles, birds, and mammals).^[1] Thus, the term mesonephros is usually reserved for the embryonic kidney of amniotes.^[1]

The mesonephros and metanephros of amniotes are derived from different parts of the anamniote opisthonephros.^[1] The metanephros is derived from the posterior part of the opisthonephros.^[1] In amniotes, most of the former opisthonephros became the epididymis, and the archinephric duct became the vas deferens.^[4]

See also

• Pronephros
• Mesonephros
• Metanephros

References

1. ^ ^{a b c d e} Juneja, Kavita (January 2002). Animal Physiology (1st ed.). Anmol Publications. ISBN 8126111666. 
2. ^ Kardong, Kenneth; Edward Zalisko (October 2008). Comparative Vertebrate Anatomy: A Laboratory Dissection Guide (5th ed.). McGraw-Hill Science/Engineering/Math. ISBN 0072970081. 
3. ^ ^{a b} Ooi EC; Youson JH (1977). "Morphogenesis and growth of the definitive opisthonephros during metamorphosis of anadromous sea lamprey, Petromyzon marinus L.". J. Embryol. exp. Morph. 42: 219–235. 
4. ^ Jurd, Richard (March 2004). BIOS Instant Notes in Animal Biology (2nd ed.). Taylor & Francis. ISBN 1859963250.