Increased expression of aquaporin-1 in the anterior temporal neocortex of patients with intractable epilepsy.
OBJECTIVE
Aquaporin-1 (AQP1), the osmotic water channel, is located in choroidal plexus, which facilitates the cerebrospinal fluid formation in central nervous system (CNS). AQP1 has been speculated to maintain the homeostasis of intracellular and extracellular water in the brain, while the intractable epilepsy (IE) may be related to the imbalance in water and ion homeostasis.


METHODS
To investigate the role of AQP1 in pathophysiology of IE, we studied the expression of AQP1 in surgical samples of the anterior temporal neocortex of patients with IE and the age-matched controls samples.


RESULTS
Using immunohistochemistry, it was shown that AQP1 expression increased in astrocytes, but not in neurons or oligodendrocytes. Double-label immunofluorescence and confocal microscopy disclosed AQP1 immunoreactivity at the astrocyte membranes, where the most abundant expression was in the perivascular glial processes, which were recognized with antiglial fibrillary acidic protein antibodies (anti-GFAP).


CONCLUSIONS
For the first time, we showed high expression of AQP1 water channels in IE cases and suggest two mechanisms to explain this finding. Increased AQP1 expression of astrocytes may be a cause or a consequence of IE. Thus, additional works are needed to elucidate the true mechanism underlying their relationship.
Department of Neurology, Qilu Hospital, Jinan 250012, China. zhoushengnian126@126.com
Shengnian
S
Zhou
Xian
X
Sun
Liqing
L
Liu
Xuefeng
X
Wang
Kunbin
K
Liu
D000293:Adolescent; D000328:Adult; D051398:Aquaporin 1 / Q000378:metabolism*; D001253:Astrocytes / Q000378:metabolism* / Q000648:ultrastructure; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D001812:Blood-Brain Barrier / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D001929:Brain Edema / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D002648:Child; D004827:Epilepsy / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D019579:Neocortex / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D013702:Temporal Lobe / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D015854:Up-Regulation / Q000502:physiology; D014882:Water-Electrolyte Balance / Q000502:physiology; D014883:Water-Electrolyte Imbalance / Q000378:metabolism / Q000503:physiopathology
D015415:Biomarkers; D051398:Aquaporin 1