Article

Temporal changes in expression of aquaporin-3, -4, -5 and -8 in rat brains after permanent focal cerebral ischemia.

Institute of Neuroscience, Chongqing Medical University, Chongqing 400016, People's Republic of China.
Brain research (impact factor: 2.46). 08/2009; 1290:121-32. DOI:10.1016/j.brainres.2009.07.018 pp.121-32
Source: PubMed

ABSTRACT Morbidity and mortality in stroke are attributed to cerebral edema. To date, six aquaporins (AQPs) have been found in rat brains. Whereas studies have been focused on AQP1, -4 and -9, little is known about the expression of AQP3, -5 and -8. To clarify roles of AQP3, -5 and -8 in water movement, we examined the expression patterns of AQP3, -5 and -8 in ischemic brains from the rats with permanent middle cerebral artery occlusion (pMCAO). We also investigated the expression of AQP4 after ischemia, which was used as a positive control. We found that the expression of AQP4 increased continuously until 24 h after pMCAO in both the ischemic core and the border region. The increased expression was correlated with brain swelling, whereas the expression of AQP3, -5 and -8 continued to increase until 24 h after pMCAO in the border region but decreased 6 h after pMCAO in the ischemic core. We also found AQPs were colocalized with GFAP-positive astrocytes and/or NeuN-positive neurons in rat brains. This is the first study describing the expression of AQP3, -5 and -8 in rat brains subjected to pMCAO. Our findings indicated that dynamic changes of AQP3, -4, -5 and -8 expression could contribute to the development of cerebral edema after brain ischemia. Besides, AQP3, -5 and -8 may be involved in the neuronal swelling.

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Keywords

-8 expression
 
AQP1
 
AQP4
 
AQPs
 
border region
 
brain ischemia
 
clarify roles
 
dynamic changes
 
expression patterns
 
GFAP-positive astrocytes
 
increased expression
 
ischemic brains
 
ischemic core
 
Morbidity
 
NeuN-positive neurons
 
permanent middle cerebral artery occlusion
 
pMCAO
 
positive control
 
rat brains
 
water movement
 

Mei Yang