Decreased hemispheric Aquaporin-4 is linked to evolving brain edema following controlled cortical impact injury in rats.
The cerebral Aquaporin-4 (AQP4) water channel is suggested to be involved in brain edema formation aggravated by reduced cerebral blood flow early after traumatic brain injury (TBI). Therefore, the temporal profile of brain edema formation, AQP4 expression, and cortical perfusion were investigated following focal TBI in rats. Brain edema was maximal by 24 h. Concurrently, AQP4 protein expression was decreased in both hemispheres, being more pronounced in the traumatized hemisphere (-50%) 48 h after trauma. Cortical perfusion was only decreased in the ipsilateral cortex (-40%) between 4 and 8 h after trauma, reaching baseline values at 24 h. Globally reduced AQP4 expression following induction of a focal contusion coincides with edema development and seems to be independent of changes in cortical perfusion.
Kiening
Karl L
KL
Department of Neurosurgery, Virchow Medical Center, Charité, Humboldt-University at Berlin, Augustenburger Platz 1, 13353 Berlin, Germany.
van Landeghem
Frank K H
FK
Schreiber
Stefan
S
Thomale
Ulrich W
UW
von Deimling
Andreas
A
Unterberg
Andreas W
AW
Stover
John F
JF
D000818:Animals; D051401:Aquaporin 4; D020346:Aquaporins / Q000378:metabolism*; D001812:Blood-Brain Barrier / Q000502:physiology; D001929:Brain Edema / Q000209:etiology* / Q000378:metabolism* / Q000503:physiopathology; D001930:Brain Injuries / Q000150:complications*; D002463:Cell Membrane Permeability / Q000502:physiology; D002540:Cerebral Cortex / Q000293:injuries / Q000378:metabolism* / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D015536:Down-Regulation / Q000502:physiology*; D005110:Extracellular Space / Q000378:metabolism; D007839:Functional Laterality / Q000502:physiology; D007424:Intracellular Fluid / Q000378:metabolism; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014882:Water-Electrolyte Balance / Q000502:physiology
C496032:Aqp4 protein, rat; D051401:Aquaporin 4; D020346:Aquaporins