title: Determinants of microvascular network topologies in implanted neovasculatures.
abstract: OBJECTIVE
  During neovascularization, the end result is a new functional microcirculation composed of a network of mature microvessels with specific topologies. Although much is known concerning the mechanisms underlying the initiation of angiogenesis, it remains unclear how the final architecture of microcirculatory beds is regulated. To begin to address this, we determined the impact of angiogenic neovessel prepatterning on the final microvascular network topology using a model of implant neovascularization.
  
  
  RESULTS
  We used 3D direct-write bioprinting or physical constraints in a manner permitting postangiogenesis vascular remodeling and adaptation to pattern angiogenic microvascular precursors (neovessels formed from isolated microvessel segments) in 3D collagen gels before implantation and subsequent network formation. Neovasculatures prepatterned into parallel arrays formed functional networks after 4 weeks postimplantation but lost the prepatterned architecture. However, maintenance of uniaxial physical constraints during postangiogenesis remodeling of the implanted neovasculatures produced networks with aligned microvessels, as well as an altered proportional distribution of arterioles, capillaries, and venules.
  
  
  CONCLUSIONS
  Here we show that network topology resulting from implanted microvessel precursors is independent from prepatterning of precursors but can be influenced by a patterning stimulus involving tissue deformation during postangiogenesis remodeling and maturation.
authors: Cardiovascular Innovation Institute, 302 E Muhammad Ali Blvd, Louisville, KY 40202, USA.
authors: Carlos C
authors: CC
authors: Chang
authors: Laxminarayanan
authors: L
authors: Krishnan
authors: Sara S
authors: SS
authors: Nunes
authors: Kenneth H
authors: KH
authors: Church
authors: Lowell T
authors: LT
authors: Edgar
authors: Eugene D
authors: ED
authors: Boland
authors: Jeffery A
authors: JA
authors: Weiss
authors: Stuart K
authors: SK
authors: Williams
authors: James B
authors: JB
authors: Hoying
mesh_terms: D000818:Animals; D001705:Bioprosthesis; D001807:Blood Vessel Prosthesis; D003198:Computer Simulation; D005583:Fourier Analysis; D008297:Male; D055806:Microvessels / Q000033:anatomy & histology* / Q000254:growth & development* / Q000502:physiology; D008955:Models, Cardiovascular; D018919:Neovascularization, Physiologic; D051381:Rats; D017207:Rats, Sprague-Dawley; D055647:Rats, Transgenic