title: Impaired angiogenesis in the enalapril-treated neonatal rat kidney.
abstract: OBJECTIVE
  Nephrogenesis is normally accompanied by a tightly regulated and efficient vascularization. We investigated the effect of angiotensin II inhibition on angiogenesis in the developing rat kidney.
  
  
  METHODS
  Newborn rat pups were treated with enalapril (30 mg/kg/day) or vehicle (control) for 7 days after birth. Renal histological changes were checked using Hematoxylin & Eosin staining. We also investigated the intrarenal expression of vascular endothelial growth factor (VEGF)-A, VEGF receptor 1 (VEGFR1), VEGFR2, platelet-derived growth factor (PDGF)-B, and PDGF receptor-β with Western blotting and immunohistochemical staining at postnatal day 8. Expression of the endothelial cell marker CD31 was examined to determine glomerular and peritubular capillary density.
  
  
  RESULTS
  Enalapril-treated rat kidneys showed disrupted tubules and vessels when compared with the control rat kidneys. In the enalapril-treated group, intrarenal VEGF-A protein expression was significantly higher, whereas VEGFR1 protein expression was lower than that in the control group (P<0.05). The expression of VEGFR2, PDGF-B, and PDGF receptor-β was not different between the 2 groups. The increased capillary CD31 expression on the western blots of enalapril-treated rat kidneys indicated that the total endothelial cell protein level was increased, while the cortical capillary density, assessed using CD31 immunohistochemical staining, was decreased.
  
  
  CONCLUSIONS
  Impaired VEGF-VEGFR signaling and altered capillary repair may play a role in the deterioration of the kidney vasculature after blocking of angiotensin II during renal development.
authors.affiliation: Department of Pediatrics, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hyung Eun
authors.initials: HE
authors.lastname: Yim
authors.affiliation: Department of Pediatrics, Korea University College of Medicine, Seoul, Korea.
authors.forename: Kee Hwan
authors.initials: KH
authors.lastname: Yoo
authors.affiliation: Department of Pediatrics, Korea University College of Medicine, Seoul, Korea.
authors.forename: Eun Soo
authors.initials: ES
authors.lastname: Bae
authors.affiliation: Department of Pediatrics, Korea University College of Medicine, Seoul, Korea.
authors.forename: Young Sook
authors.initials: YS
authors.lastname: Hong
authors.affiliation: Department of Pediatrics, Korea University College of Medicine, Seoul, Korea.
authors.forename: Joo Won
authors.initials: JW
authors.lastname: Lee
keywords: Angiotensin II; Growth and development; Vascular remodeling