title: [The Involvement of CRMP-2 on Axonal and Dendrictic Injury after Hypoxic-Ischemic Brain Injury in Neonatal Rat].
abstract: OBJECTIVE
  To investigate the activity of collapsin response mediator protein 2 (CRMP-2) and its possible regulation for axonal and dendrictic injury under hypoxia-ischemia (HI).
  
  
  METHODS
  Postnatal day 10 SD rats were suffered the right common carotid artery ligation and 8% mixture of oxygen and nitrogen hypoxia 2.5 h to produce HI model. The expression of total and phosphorylated CRMP-2 and amyloid precursor protein (APP) were detected by Western blot after HI. After pretreatment of protein kinase B (Akt) inhibitor, wortmannin or LY294002, western blot and immunohistochemistry were applied to detect the expression of total and phosphorylated of CRMP-2 at 4 h and 24 h after HI. At 72 h after HI, APP was detected by Western blot and immunohistochemistry, axonal and dendrictic injury was determined by electron microscope.
  
  
  RESULTS
  Total CRMP-2 was not obviously changed after HI, compared with that of sham controls. However, the phosphorylated CRMP-2 (p-CRMP-2) protein transiently increased at 0.5 h, started to decrease at 2 h, remained at a low level at the rest of the time points, compared with that of sham controls. APP protein started to increase at 2 h, remained at a high level at 4, 8, 24 h, and then progressively increased at 48 and 72 h. In wortmannin and LY294002 group, CRMP-2 protein was not obviously changed at 4 h and 24 h after HI. However, p-CRMP-2 increased at 4 h and 24 h. At 72 h, wortmannin pretreatment increased APP expression, leading to more severe ultrastructure failure of axon and dendrite.
  
  
  CONCLUSIONS
  As a downstream effector of Akt pathway, CRMP-2 is involved in axonal and dendritic injury regulation after HI in neonatal rat.
authors.forename: Tao
authors.initials: T
authors.lastname: Xiong
authors.forename: Hong-ju
authors.initials: HJ
authors.lastname: Chen
authors.forename: Yi
authors.initials: Y
authors.lastname: Qu
authors.forename: De-zhi
authors.initials: DZ
authors.lastname: Mu
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001369:Axons / Q000378:metabolism / Q000473:pathology*; D015153:Blotting, Western; D002867:Chromones; D003712:Dendrites / Q000378:metabolism / Q000473:pathology*; D000860:Hypoxia; D020925:Hypoxia-Ischemia, Brain / Q000378:metabolism*; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D009025:Morpholines; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010766:Phosphorylation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D002867:Chromones; D036341:Intercellular Signaling Peptides and Proteins; D009025:Morpholines; D009419:Nerve Tissue Proteins; C095114:collapsin response mediator protein-2; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one