Neurochemical Research

, Volume 40, Issue 6, pp 1121–1132 | Cite as

Activation of mGluR5 Attenuates Microglial Activation and Neuronal Apoptosis in Early Brain Injury After Experimental Subarachnoid Hemorrhage in Rats

  • Zong-yong ZhangEmail author
  • Bao-liang Sun
  • Jun-ke Liu
  • Ming-feng Yang
  • Da-wei Li
  • Jie Fang
  • Shuai Zhang
  • Qi-lin Yuan
  • Si-luo HuangEmail author
Original Paper


Activation of metabotropic glutamate receptor 5 (mGluR5) provided neuroprotection in multiple central nervous system injury, but the roles of mGluR5 in subarachnoid hemorrhage (SAH) remain unclear. In present study, we aimed to evaluate whether activation of mGluR5 attenuates early brain injury (EBI) after experimental SAH in rats. We found that selective mGluR5 orthosteric agonist CHPG or positive allosteric modulator VU0360172 administration significantly improves neurological function and attenuates brain edema at 24 h after SAH. Furthermore, mGluR5 obviously expresses in activated microglia (ED-1 positive) after SAH. CHPG or VU0360172 administration significantly reduces the numbers of activated microglia and the protein and mRNA levels of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α at 24 h after SAH. Moreover, CHPG or VU0360172 administration obviously reduces the number of TUNEL-positive cells and active caspase-3/NeuN-positive neurons in cortex at 24 h after SAH. CHPG or VU0360172 administration significantly up-regulates the expression of Bcl-2, and down-regulates the expression of Bax and active caspase-3, which in turn increases the ratio of Bcl-2/Bax. Our results indicate that activation of mGluR5 attenuates microglial activation and neuronal apoptosis, and improves neurological function in EBI after SAH.


Subarachnoid hemorrhage mGluR5 Early brain injury Microglia activation Neuronal apoptosis 



The National Natural Science Foundation of China (NSFC) (No. 81301018, No. 81271275 and No. 31100548) supported this work.

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Zong-yong Zhang
    • 1
    Email author
  • Bao-liang Sun
    • 1
  • Jun-ke Liu
    • 2
  • Ming-feng Yang
    • 1
  • Da-wei Li
    • 1
  • Jie Fang
    • 1
  • Shuai Zhang
    • 1
  • Qi-lin Yuan
    • 2
  • Si-luo Huang
    • 2
    Email author
  1. 1.Key Lab of Cerebral Microcirculation at the Universities of ShandongLife Science Research Centre of Taishan Medical UniversityTaianChina
  2. 2.Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanChina

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