Article

Aquaporin-4-dependent edema clearance following status epilepticus

Department of Neurological Surgery, University of California, Davis, CA, United States.
Epilepsy research (Impact Factor: 2.19). 02/2012; 98(2-3):264-8. DOI: 10.1016/j.eplepsyres.2011.09.016
Source: PubMed

ABSTRACT We investigated the role of aquaporin-4 in the development of cerebral edema following kainic acid-induced status epilepticus (SE) using specific gravimetry and T2 MRI techniques at 6 h, 1 day, 4 days and 7 days after SE. Our results indicate significantly greater tissue edema and T2 MRI changes in AQP4(-/-) compared to AQP4(+/+) mice that peaks at about 1 day after SE (greater in hippocampus relative to cortex). These results have implications for the mechanisms of edema formation and clearance following intense seizure activity.

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    • "ct BBB ( Manley et al . , 2000 ; Papadopoulos and Verkman , 2013 ) . It is of interest that in vasogenic edema , AQP4 plays an oppos - ing role . In established models of BBB disruption such as cortical freeze injury , brain tumor , brain abscess ( Bloch et al . , 2005 ) , sub - arachnoid hemorrhage ( Tait et al . , 2010 ) and status epilepticus ( Lee et al . , 2012 ) , AQP4 - null mice develop more edema than do wild - type mice . This increased vasogenic component from dele - tion of AQP4 reaffirms that vasogenic elimination of water into the CSF and blood occurs via AQP4 - dependent routes ( Saadoun and Papadopoulos , 2010 ; Papadopoulos and Verkman , 2013 ) . AQP4 mediates bidirectional water f"
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