title: The hippocampal neurovascular niche during normal development and after irradiation to the juvenile mouse brain.
abstract: OBJECTIVE
  To investigate the effects of cranial irradiation on the neurovascular niche in the young brain. Disruption of this niche has previously been observed in the adult rat brain after irradiation.
  
  
  METHODS
  We subjected postnatal day 14 (P14) mice to a single dose of 8 Gy whole brain irradiation and measured the distance between microvessels and either neural progenitor cells (doublecortin-positive, DCX(+)) or proliferating cells (Ki-67(+)) in the dorsal hippocampal subgranular zone (SGZ) 6 hours, 1 week and 7 weeks post-irradiation. In addition, pericyte coverage of microvessels in the SGZ was measured.
  
  
  RESULTS
  DCX(+) and Ki-67(+) cells were located closer to microvessels in the adult brain compared to young, still growing brains, constituting new information on normal development. We found an increased distance between microvessels and DCX(+) cells 6 h post-irradiation and between microvessels and Ki-67(+) cells 1 week post-irradiation. Furthermore, pericyte coverage was transiently decreased by 17% 6 h post-irradiation.
  
  
  CONCLUSIONS
  The hippocampal neurovascular niche in the young, growing brain is transiently disrupted by irradiation. It remains to be elucidated what role these transient changes play in the apparently permanent ablation of hippocampal neurogenesis previously demonstrated in the same model.
authors.affiliation: Center for Brain Repair and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg , Gothenburg.
authors.forename: Martina
authors.initials: M
authors.lastname: Boström
authors.forename: Nina
authors.initials: N
authors.lastname: Hellström Erkenstam
authors.forename: David
authors.initials: D
authors.lastname: Kaluza
authors.forename: Lars
authors.initials: L
authors.lastname: Jakobsson
authors.forename: Marie
authors.initials: M
authors.lastname: Kalm
authors.forename: Klas
authors.initials: K
authors.lastname: Blomgren
mesh_terms: D000818:Animals; D001921:Brain / Q000254:growth & development / Q000528:radiation effects*; D016923:Cell Death; D049109:Cell Proliferation; D018891:Dentate Gyrus / Q000528:radiation effects; D000089662:Doublecortin Protein; D006624:Hippocampus / Q000254:growth & development / Q000528:radiation effects*; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008833:Microcirculation; D055495:Neurogenesis / Q000502:physiology*; D009474:Neurons / Q000528:radiation effects; D010315:Particle Accelerators; D020286:Pericytes / Q000166:cytology; D011878:Radiotherapy; D051381:Rats; D013997:Time Factors
chemical_list: C000714847:Dcx protein, mouse; C000714848:Dcx protein, rat; D000089662:Doublecortin Protein; D019394:Ki-67 Antigen
keywords: Brain development; endothelium; neurogenesis; neurovascular unit; pericyte; radiation therapy