title: Intussusceptive angiogenesis and expression of Tie receptors during porcine metanephric kidney development.
abstract: Intussusceptive angiogenesis (IA) is required for normal embryonic vascular development. The Tie family of receptors and their ligands, the angiopoietins, play an important role in the growth or regression of blood vessels which are important not only during development but also throughout an organism's life. The presence of IA was investigated in glomerular capillaries of the fetal porcine metanephros using Mercox II resin casts. The first signs of IA were observed in stage III glomeruli. Stage IV and V glomeruli showed numerous signs of aligned pillar formation and their successive merging to delineate the vascular entities. Furthermore, immunohistochemistry was used to determine the exact locations of the Tie receptors in the developing porcine metanephric kidneys. Tie1 and Tie2 were found in endothelial cells of all glomeruli. Strong expression of the receptors was found in podocytes of stage V glomeruli whereas a weaker expression was observed in the cuboidal epithelial cells of stage III and IV glomeruli. Remarkably, the receptors were also found in the parietal epithelium of Bowman's capsule. These findings indicate that there might be an association between the Tie receptors and the IA during porcine metanephric development and during glomerulogenesis in particular.
authors.affiliation: Department of Morphology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan, Merelbeke, Belgium. anastasia.logothetidou@ugent.be.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Logothetidou
authors.affiliation: Department of Morphology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan, Merelbeke, Belgium.
authors.forename: Tim
authors.initials: T
authors.lastname: Vandecasteele
authors.affiliation: Department of Morphology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan, Merelbeke, Belgium.
authors.forename: Els
authors.initials: E
authors.lastname: Van Mulken
authors.affiliation: Department of Morphology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan, Merelbeke, Belgium.
authors.forename: Kimberley
authors.initials: K
authors.lastname: Vandevelde
authors.affiliation: Department of Morphology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan, Merelbeke, Belgium.
authors.forename: Pieter
authors.initials: P
authors.lastname: Cornillie
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000196:embryology* / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology; D007150:Immunohistochemistry; D007668:Kidney / Q000098:blood supply* / Q000196:embryology*; D007678:Kidney Glomerulus / Q000098:blood supply / Q000196:embryology; D009024:Morphogenesis; D018919:Neovascularization, Physiologic; D038081:Organogenesis; D042810:Receptor, TIE-1 / Q000378:metabolism*; D042787:Receptor, TIE-2 / Q000378:metabolism*; D013552:Swine
chemical_list: D042810:Receptor, TIE-1; D042787:Receptor, TIE-2