title: Role of acid-sensing ion channel 1a in the secondary damage of traumatic spinal cord injury.
abstract: OBJECTIVE
  To determine the cellular and molecular mechanisms by which acid-sensing ion channel 1a (ASIC1a) plays its role in the secondary injury after traumatic spinal cord injury (SCI), and validate the neuroprotective effect of ASIC1a suppression in SCI model in vivo.
  
  
  BACKGROUND
  Secondary damage after traumatic SCI contributes to the exacerbation of cellular insult and thereby contributes to spinal cord dysfunction. However, the underlying mechanisms remain largely unknown. Acidosis is commonly involved in the secondary injury process after the injury of central nervous system, but whether ASIC1a is involved in secondary injury after SCI is unclear.
  
  
  METHODS
  Male Sprague-Dawley rats were subjected to spinal contusion using a weight-drop injury approach. Western blotting and immunofluorescence assays were used to observe the change of ASIC1a expression after SCI. The TUNEL staining in vivo as well as the cell viability and death assays in spinal neuronal culture were employed to assess the role of ASIC1a in the secondary spinal neuronal injury. The electrophysiological recording and Ca(2+) imaging were performed to reveal the possible underlying mechanism. The antagonists and antisense oligonucleotide for ASIC1a, lesion volume assessment assay and behavior test were used to estimate the therapeutic effect of ASIC1a on SCI.
  
  
  RESULTS
  We show that ASIC1a expression is markedly increased in the peri-injury zone after traumatic SCI. Consistent with the change of ASIC1a expression in injured spinal neurons, both ASIC1a-mediated whole-cell currents and ASIC1a-mediated Ca(2+) entry are significantly enhanced after injury. We also show that increased activity of ASIC1a contributes to SCI-induced neuronal death. Importantly, our results indicate that down-regulation of ASIC1a by antagonists or antisense oligonucleotide reduces tissue damage and promotes the recovery of neurological function after SCI.
  
  
  CONCLUSIONS
  This study reveals a cellular and molecular mechanism by which ASIC1a is involved in the secondary damage process after traumatic SCI. Our results suggest that blockade of Ca(2+) -permeable ASIC1a may be a potential neuroprotection strategy for the treatment of SCI patients.
authors: Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital, Third Military Medical University, Chongqing, China.
authors: Rong
authors: R
authors: Hu
authors: Bo
authors: B
authors: Duan
authors: Dianshi
authors: D
authors: Wang
authors: Ye
authors: Y
authors: Yu
authors: Weiguang
authors: W
authors: Li
authors: Haishui
authors: H
authors: Luo
authors: Peigang
authors: P
authors: Lu
authors: Jiangkai
authors: J
authors: Lin
authors: Gang
authors: G
authors: Zhu
authors: Qi
authors: Q
authors: Wan
authors: Hua
authors: H
authors: Feng
mesh_terms: D062565:Acid Sensing Ion Channels; D000138:Acidosis / Q000473:pathology*; D000818:Animals; D015153:Blotting, Western; D015220:Calcium Channels / Q000502:physiology; D016923:Cell Death / Q000502:physiology; D020287:In Situ Nick-End Labeling; D008297:Male; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D009419:Nerve Tissue Proteins / Q000032:analysis* / Q000037:antagonists & inhibitors / Q000502:physiology*; D009474:Neurons / Q000473:pathology / Q000502:physiology; D020319:Oligodeoxyribonucleotides, Antisense / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D015222:Sodium Channels / Q000032:analysis* / Q000502:physiology*; D013116:Spinal Cord / Q000473:pathology* / Q000503:physiopathology*; D013119:Spinal Cord Injuries / Q000473:pathology* / Q000503:physiopathology*; D015854:Up-Regulation / Q000502:physiology
chemical_list: D062565:Acid Sensing Ion Channels; D015220:Calcium Channels; D009419:Nerve Tissue Proteins; D020319:Oligodeoxyribonucleotides, Antisense; D015222:Sodium Channels