[Hypoxia/reoxygenation induced endoplasmic reticulum stress in cultured neonatal rat cardiomyocyte].
OBJECTIVE
To investigate the effect of hypoxia/reoxygenation on endoplasmic reticulum stress in cultured neonatal rat cardiomyocytes.


METHODS
Neonatal rat cardiac myocytes in primary culture were exposed to hypoxia for 5.5 hours and subsequently reoxygenation for 2-24 hours. Western blot and RT-PCR were applied to monitor the expression change of GRP78 (glucose regulated protein 78). 2-deoxy-D-glucose (2-DG) was the positive control of this study. Then Western blot and RT-PCR were used to examine the expression of GRP78.


RESULTS
Cell viability was decreased obviously after hypoxia/reoxygenation. Compared with untreated cells, the GRP78 content of the cells had increased significantly in the hypoxia/reoxygenation cells. The level of GRP78 protein and mRNA elevated from the points of 2 hours to 24 hours after reoxygenation, and increased most obviously at the point of 4 hours after reoxygenation. (4 hours: protein level 142% of the control, mRNA level 200%). 2-DG could induce the increasing expression of GRP78 in a concentration-dependent manner from 10-50 mmol/L.


CONCLUSIONS
Hypoxia/reperfusion can induce endoplasmic reticulum stress in rat cardiomyocytes.
Ma
Qing-bian
QB
Department of Cardiology, Peking University Third Hospital, Beijing 100083, China.
Gao
Wei
W
Guo
Yan-hong
YH
Zhao
Chun-yu
CY
Xue
Lin
L
Tang
Chao-shu
CS
D000818:Animals; D000831:Animals, Newborn; D015687:Cell Hypoxia; D002478:Cells, Cultured; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000096:biosynthesis* / Q000235:genetics; D018832:Molecular Chaperones / Q000096:biosynthesis* / Q000235:genetics; D015428:Myocardial Reperfusion Injury / Q000378:metabolism*; D032383:Myocytes, Cardiac / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological / Q000378:metabolism; D000091342:Endoplasmic Reticulum Chaperone BiP
D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; C051684:GRP78 protein, rat; D000091342:Endoplasmic Reticulum Chaperone BiP