title: Cell proliferation and morphometric changes in the rat kidney during postnatal development.
abstract: We have investigated the temporal maturation of the rat kidney during the postnatal developmental period. As a result, we observed the following: an active process of cortical cell proliferation and differentiation occurs as late as day 20. The medulla is the most immature zone at birth and displays the greatest morphological changes during this period. At birth, no distinction exists between inner and outer medulla, and the outer and inner strip of the outer medulla can be distinguished as late as day 30. Remodeling of the ECM surrounding collecting ducts occurs in the medulla twice, stopping at day 11 and it occurs in the papilla three times, stopping at day 20. The increase of kidney size is temporally different for each kidney zone. The cortex and the papilla acquire the morphological appearance of the adult kidney before the medulla does. Consequently, the medulla remains at the highest degree of immaturation among the kidney zones for a relatively long postnatal period.
authors.affiliation: Laboratory of Cellular Biology and Histology, Department of Biological Sciences, Faculty of Pharmacy and Biochemistry, University of Buenos Aires, IQUIFIB-CONICET, Buenos Aires, Argentina.
authors.forename: María Gabriela
authors.initials: MG
authors.lastname: Márquez
authors.forename: Isabel
authors.initials: I
authors.lastname: Cabrera
authors.forename: Diego Javier
authors.initials: DJ
authors.lastname: Serrano
authors.forename: Norma
authors.initials: N
authors.lastname: Sterin-Speziale
mesh_terms: D000818:Animals; D002455:Cell Division / Q000502:physiology; D004847:Epithelial Cells / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D005260:Female; D006031:Glycosylation; D007672:Kidney Cortex / Q000166:cytology* / Q000254:growth & development*; D007679:Kidney Medulla / Q000166:cytology* / Q000254:growth & development*; D037102:Lectins / Q000378:metabolism / Q000494:pharmacology; D008297:Male; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar
chemical_list: D037102:Lectins; D018809:Proliferating Cell Nuclear Antigen