title: [Changes of NGFI-B subcellular location in cardiomyocytes of stressed rats and its biological effects].
abstract: OBJECTIVE
  To investigate the changes of expression and subcellular location of nuclear growth-induced protein-B(NGFI-B) in cardiomyocytes of stressed rats and its biological effect and to provide scientific evidences for exploring the mechanism underlying myocardium injury induced by stress.
  
  
  METHODS
  The cell model of stress-induced cardiomyocyte injury were established. Western blot method and confocal microscopy method were used to investigate the subcellular location of NGFI-B in cardiomyocytes under stress. The flow-cytometry was selected to detect the apoptotic rate in cardiomyocytes in vitro. Western blot method was used to determine the content of cytochrome C protein in mitochondria and cytoplasm respectively.
  
  
  RESULTS
  Stress induced the increase of NGFI-B content in the mitochondria of cardiomyocytes and the translocation of NGFI-B from the nucleus to the mitochondria. The translocation of NGFI-B promoted the release of cytochrome C from the mitochondria and the cardiomyocyte apoptosis. Treatment of stressed cardiomyocytes with leptomycin B, a non-specific blocker of nuclear export, resulted in nuclear retention of NGFI-B and abrogated its ability to induce the release of cytochrome C from the mitochondria.
  
  
  CONCLUSIONS
  Stress could induce NGFI-B translocation from the nucleus to the mitochondria in cardiomyocytes, which activated the mitochondrial pathway of cell apoptosis.
authors.affiliation: Department of Health and Exercise, Tianjin University of Sport, Tianjin 300381, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Feng
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Rui
authors.initials: R
authors.lastname: Zhan
authors.forename: Xin-xing
authors.initials: XX
authors.lastname: Wang
authors.forename: Ling-jia
authors.initials: LJ
authors.lastname: Qian
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis; D002478:Cells, Cultured; D008297:Male; D032383:Myocytes, Cardiac / Q000166:cytology / Q000378:metabolism*; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1 / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological
chemical_list: C539820:Nr4a1 protein, rat; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1