title: Permeability and distribution of nerve growth factor in the brain of neonatal rats by periphery venous injection in hypoxic-ischemic state.
abstract: OBJECTIVE
  To investigate the permeability of β-NGF through blood-brain-barrier (BBB) in neonatal and adult rats, and the spatial distribution of β-NGF in different brain regions in hypoxic-ischemic (HI) and normal neonatal rats.
  
  
  METHODS
  To investigate the overall permeability of β-NGF through BBB, β-NGF labeled with I125was injected into adult rats, neonatal rats and HI neonatal rats via tail vein. The radioactivity of brain tissue and blood was examined and analyzed 30 min after injection. Also, brain regions including the basal forebrain, frontal cortex, hippocampus, hypothalamus, cerebellum, bulbus olfactorius and hypophysis, of all the rats were dissected and radioactivity was examined to investigate the spatial specificity of NGF permeation through BBB.
  
  
  RESULTS
  Statistically significant results were observed in I125-β-NGF contents in brain tissues of adult rats group, neonatal rats group and HI neonatal rats group (P < 0.05). Compared to the HI neonatal rats' brain with the highest I125-β-NGF contents, normal neonatal rats ranks the second while the adult rats were the lowest. While for the spatial specificity examination part, I125-β-NGF in both HI group and control group were widely distributed in basal forebrain, frontal cortex, hippocampus, cerebellum and bulbus olfactorius. But the radioactivity in frontal cortex, hippocampus and cerebellum of HI groups are statistically higher than control groups (P < 0.05).
  
  
  CONCLUSIONS
  β-NGF can more easily penetrate the BBB of newborn rats than adult rats via peripheral venous administration and this effect can be enhanced by HI insult. Also, this HI-induced permeation of β-NGF through BBB is more obvious in frontal cortex, hippocampus and cerebellum.
authors.affiliation: Department of Neonatology, The First Hospital of Jilin University, 71 Xinmin Street, Changchun, 130021 Jilin China.
authors.forename: Wenli
authors.initials: W
authors.lastname: Zhou
authors.affiliation: Department of Colorectal and Anal Surgery, The First Hospital of Jilin University, Changchun, 130021 Jilin China.
authors.forename: Jiantao
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, The First Hospital of Jilin University, Changchun, 130021 Jilin China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Wang
authors.affiliation: Department of Colorectal and Anal Surgery, The First Hospital of Jilin University, Changchun, 130021 Jilin China.
authors.forename: Limian
authors.initials: L
authors.lastname: Ling
authors.affiliation: Department of Neonatology, The First Hospital of Jilin University, 71 Xinmin Street, Changchun, 130021 Jilin China.
authors.forename: Chaoying
authors.initials: C
authors.lastname: Yan
keywords: Blood–brain barrier; Hypoxic; Ischemic; Nerve growth factor