Cellular and Molecular Neurobiology

, Volume 33, Issue 3, pp 401–410

The Role of Connexin 43 and Hemichannels Correlated with the Astrocytic Death Following Ischemia/Reperfusion Insult

  • Xueyu Wang
  • Aihua Ma
  • Weiwei Zhu
  • Liping Zhu
  • Yutian Zhao
  • Jiashui Xi
  • Xinying Zhang
  • Bojun Zhao
  • David L. Becker
Original Research


The aim of this study was to investigate the role of connexin 43 (Cx43) and its hemichannel (HC1) in the death of astrocytes following ischemia/reperfusion (IR) or oxygen–glucose deprivation/reoxygenation (OGDR) insult. Wistar rats had their bilateral common carotid artery clamped for 1.5 h followed by 0, 4, and 24 h of reperfusion (n = 8 for each time point), respectively. All rats were sacrificed and Cx43, HC1, and caspase 3 (Casp3) in cerebral ischemic tissues were examined by immunohistochemistry and western blotting. Astrocytes cell line, astrocytes transduced with a retroviral empty vector (Psup astrocyte), or a Cx43-specific shRNA construct (shRNA astrocytes) were treated with OGDR insult for various periods. The viability of astrocytes was assessed by MTT assay. The expression of Cx43, HC1, and Casp3 was detected with western blotting. The results showed that the expression of Cx43, HC1, and Casp3 in rats’ brain, astrocytes, and Psup astrocytes was significantly increased after 4 h of IR/OGDR and recovered on 24 h of the insult. Cell viability decreased after 4 h of the insult whereas the cell viability increased on 24 h after the insult. In contrast, the expression of Cx43, HC1, Casp3, and cell viability had no statistical differences in the null Cx43 gene—shRNA transfected astrocytes after the treatment of OGDR. The results suggest that Cx43 and HC1 are likely to play the pivotal roles in the mediation of the astrocytic death.


Gap junction Hemichannels Astrocytes Ischemia/reperfusion (IR) Oxygen–glucose deprivation/reoxygenation (OGDR) 


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Xueyu Wang
    • 1
  • Aihua Ma
    • 1
  • Weiwei Zhu
    • 2
  • Liping Zhu
    • 1
  • Yutian Zhao
    • 3
  • Jiashui Xi
    • 1
  • Xinying Zhang
    • 1
  • Bojun Zhao
    • 1
  • David L. Becker
    • 4
  1. 1.Division of Neurology, Department of PediatricsProvincial Hospital Affiliated to Shandong UniversityJinanChina
  2. 2.Department of PediatricsCentral Hospital of Jinan Affiliated to Shandong UniversityJinanChina
  3. 3.School of Pharmacy, Cardiff UniversityCardiffUK
  4. 4.Department of Cell & Development BiologyUniversity College LondonLondonUK

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