These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Expression of hypoxia-inducible transcription factors in developing human and rat kidneys.
    Author: Bernhardt WM, Schmitt R, Rosenberger C, Münchenhagen PM, Gröne HJ, Frei U, Warnecke C, Bachmann S, Wiesener MS, Willam C, Eckardt KU.
    Journal: Kidney Int; 2006 Jan; 69(1):114-22. PubMed ID: 16374431.
    Abstract:
    Early kidney development is associated with the coordinated branching of the renal tubular and vascular system and hypoxia has been proposed to be a major regulatory factor in this process. Under low oxygen levels, the hypoxia-inducible transcription factor (HIF) regulates the expression of genes involved in angiogenesis, erythropoiesis and glycolysis. To investigate the role of HIF in kidney development, we analyzed the temporal and spatial expression of the oxygen regulated HIF-1alpha and -2alpha subunits at different stages of rat and human kidney development. Using double-staining procedures, localization of the HIF target geneproducts vascular endothelial growth factor (VEGF) and endoglin was studied in relation to HIFalpha. In both species, we found marked nuclear expression of HIF-1alpha in medullary and cortical collecting ducts and in glomerular cells. In contrast, HIF-2alpha was expressed in interstitial and peritubular cells podocytes of the more mature glomeruli. After completion of glomerulogenesis and nephrogenesis, HIF-1alpha and -2alpha were no longer detectable. The HIF-target gene VEGF colocalized with HIF-1alpha protein in glomeruli and medullary collecting ducts. HIF-2alpha colocalized with the endothelium-associated angiogenic factor, endoglin. Both HIFalpha isoforms are activated in the developing kidney in a cell-specific and temporally controlled manner, indicating a regulatory role of oxygen tension in nephrogenesis. HIF-1alpha seems to be primarily involved in tubulogenesis and HIF-2alpha in renal vasculogenesis. Both isoforms are found in glomerulogenesis, potentially having synergistic effects.
    [Abstract] [Full Text] [Related] [New Search]