Role of matrix metalloproteinase-9 in apoptosis of hippocampal neurons in rats during early brain injury after subarachnoid hemorrhage.
This study investigated the possible involvement of matrix metalloproteinase 9 (MMP-9) in early brain injury (EBI) of subarachnoid hemorrhage (SAH) in rats. MMP-9 activities in hippocampus were examined at 6, 12, 24, 48 and 72 h after SAH. Laminin was detected by immunohistochemistry. Apoptosis of neurons in hippocampus was observed by TUNEL. Brain water content was also examined. MMP-9 activity and the number of apoptotic neurons increased from 12 to 72 h with a peak at 24 h. Laminin was found to decrease at 12 h, reached minimum at 24 h and began to increase from 48 h, which had a negative correlation with apoptotic neurons. The changes of brain water content were found to be coincidence with that of neuronal apoptosis. Our findings suggest that MMP-9 is probably involved in the pathophysiological events of EBI after SAH, through degrading laminin which leads to neuronal anoikis of hippocampus.
Guo
Zongduo
Z
Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China. stonegzd@gmail.com
Sun
Xiaochuan
X
He
Zhaohui
Z
Jiang
Yong
Y
Zhang
Xiaodong
X
D000818:Animals; D023102:Anoikis / Q000502:physiology; D017209:Apoptosis / Q000502:physiology*; D001834:Body Water / Q000502:physiology; D001927:Brain Diseases / Q000503:physiopathology; D004195:Disease Models, Animal; D006624:Hippocampus / Q000503:physiopathology*; D007797:Laminin / Q000378:metabolism; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D009474:Neurons / Q000502:physiology*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013345:Subarachnoid Hemorrhage / Q000503:physiopathology*; D013997:Time Factors
D007797:Laminin; D020780:Matrix Metalloproteinase 9