title: Nephron-specific expression of components of the renin-angiotensin-aldosterone system in the mouse kidney.
abstract: BACKGROUND
  The renin-angiotensin-aldosterone system (RAAS) plays an integral role in the regulation of blood pressure, electrolyte and fluid homeostasis in mammals. The capability of the different nephron segments to form components of the RAAS is only partially known. This study therefore aimed to characterize the nephron-specific expression of RAAS components within the mouse kidney.
  
  
  METHODS
  Defined nephron segments of adult C57B/16 mice were microdissected after collagenase digestion. The gene expression of renin, angiotensinogen (AGT), angiotensin-converting enzyme (ACE), angiotensin II receptors 1a (AT1a), 1b (AT1b), and 2 (AT2) was assessed by reverse transcriptase polymerase chain reaction (RT-PCR).
  
  
  RESULTS
  Renin mRNA was present in glomeruli, in proximal tubules, in distal convoluted tubules (DCT) and cortical collecting ducts (CCD). AGT mRNA was found in proximal tubules, descending thin limb of Henle's loop (dTL) and in the medullary part of the thick ascending limb (mTAL). ACE mRNA was not detectable in microdissected mouse nephron segments. AT1a, AT1b and AT2 mRNA was detected in glomeruli and proximal convoluted tubules.
  
  
  CONCLUSIONS
  Our data demonstrate a nephron-specific distribution of RAAS components. All components of the local RAAS - except ACE - are present in proximal convoluted tubules, emphasizing their involvement in sodium and water handling.
authors.affiliation: Klinik und Poliklinik für Innere Medizin II, University of Regensburg, Regensburg, Germany.
authors.forename: Stephan W
authors.initials: SW
authors.lastname: Reinhold
authors.forename: Bernd
authors.initials: B
authors.lastname: Krüger
authors.forename: Caroline
authors.initials: C
authors.lastname: Barner
authors.forename: Flavius
authors.initials: F
authors.lastname: Zoicas
authors.forename: Martin C
authors.initials: MC
authors.lastname: Kammerl
authors.forename: Ute
authors.initials: U
authors.lastname: Hoffmann
authors.forename: Tobias
authors.initials: T
authors.lastname: Bergler
authors.forename: Bernhard
authors.initials: B
authors.lastname: Banas
authors.forename: Bernhard K
authors.initials: BK
authors.lastname: Krämer
mesh_terms: D000808:Angiotensinogen / Q000235:genetics / Q000378:metabolism; D000818:Animals; D017931:DNA Primers / Q000378:metabolism; D007685:Kidney Tubules, Collecting / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D042282:Microdissection; D009399:Nephrons / Q000201:enzymology / Q000378:metabolism*; D009928:Organ Specificity / Q000235:genetics; D007703:Peptidyl-Dipeptidase A / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D044140:Receptor, Angiotensin, Type 1 / Q000235:genetics / Q000378:metabolism; D044139:Receptor, Angiotensin, Type 2 / Q000235:genetics / Q000378:metabolism; D012083:Renin / Q000235:genetics / Q000378:metabolism; D012084:Renin-Angiotensin System / Q000235:genetics*
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2; D000808:Angiotensinogen; D007703:Peptidyl-Dipeptidase A; D012083:Renin