title: [Role of P38 signaling pathway in neonatal rat astrocyte swelling and aquaporin-4 expression after oxygen-glucose deprivation and recovery].
abstract: OBJECTIVE
  To explore the role of P38 signaling pathway in neonatal rat astrocyte swelling and the expression of aquaporin-4 (AQP4) after oxygen-glucose deprivation (OGD) and recovery (OGD/R).
  
  
  METHODS
  Primarily cultured neonatal rat astrocytes were subject to OGD for 5 h followed by oxygen-glucose recovery in the presence or absence of the P38 inhibitor SB203580 (10 µmol/L). The astrocytes were investigated at 0.5, 2, 8 and 24 h after oxygen-glucose recovery for morphological changes and cell injuries using lactate dehydrogenase (LDH) assay. The expressions of P38, P-P38, and AQP4 mRNAs and proteins in the astrocytes were detected using RT-PCR and Western blotting.
  
  
  RESULTS
  OGD/R caused significantly enhanced expression of P-P38 protein, and this effect was blocked by SB203580. AQP4 mRNA and protein expression declined transiently at 0.5 h after OGD and increased gradually to reach the peak level at 8 h (P<0.05). Application of the SB203580 significantly lowered OGD-induced AQP4 mRNA and protein up-regulation (P<0.05). Astrocyte swelling occurred after OGD/R but was obviously lessened by SB203580. LDH release increased markedly after OGD/R, and was attenuated by treatment with SB203580 (P<0.01).
  
  
  CONCLUSIONS
  P38 signaling pathway participates in astrocyte swelling after OGD/R, and blocking this pathway can attenuate AQP4 up-regulation and ameliorate the cell swelling.
authors.affiliation: Department of Neurosurgery, Chongqing Medical University, Chongqing, China.
authors.forename: Zhaohua
authors.initials: Z
authors.lastname: Tang
authors.forename: Zhengbu
authors.initials: Z
authors.lastname: Liao
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Xie
authors.forename: Quanhong
authors.initials: Q
authors.lastname: Shi
authors.forename: Chaohui
authors.initials: C
authors.lastname: He
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhan
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D051401:Aquaporin 4 / Q000378:metabolism*; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology*; D001929:Brain Edema / Q000378:metabolism / Q000473:pathology; D015687:Cell Hypoxia; D005947:Glucose / Q000494:pharmacology; D020935:MAP Kinase Signaling System / Q000502:physiology*; D010100:Oxygen / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000378:metabolism*
chemical_list: C496032:Aqp4 protein, rat; D051401:Aquaporin 4; D005947:Glucose; D010100:Oxygen