TY - JOUR
T1 - Astroglial swelling for removed rat brain enlargement incubated in deoxygenated mock cerebrospinal fluid
AU - Osada, Takashi
AU - Tomita, Minoru
AU - Tanahashi, Norio
AU - Takeda, Hidetaka
AU - Nagai, Toshihiro
AU - Suzuki, Norihiro
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2006
Y1 - 2006
N2 - The source and target of edema fluid for ischemic brain swelling clinically often observed in "malignant infarction" was examined in ex vivo. Wister rat brain hemispheres were removed and incubated air-tightly in a deoxygenated artificial cerebrospinal fluid at 37°for 30 min. Ionic movement into the brain tissue was calculated from their concentration changes in the incubation fluid. We found a weight increase by 11.3±2.5% (p<0.01) and a decrease in Na+ from 148.0 to 139.0±8.2 mEq/l (p<0.01) and an increase in K+ from 4.3 to 11.2±1.2 mEq/l. Video tape recording revealed that the brain swelling started immediately upon the incubation, and the electronmicroscopical investigation of the swollen cortical tissue revealed that the fluid moved mainly into astroglial cells. The astroglial swelling was quite similar to that of specimen taken from clinical cases at autopsy. The driving force of the water shift can be explained by discharge of thermodynamic potential, i.e., a coupled transport of water with Na+ across the cell membrane (anomalous osmosis). The swelling was not affected by addition of aquaporin blocker, mercuric chloride. It is concluded that cerebrospinal fluid bathing the brain in situ can be the source of edema fluid for ischemic brain swelling.
AB - The source and target of edema fluid for ischemic brain swelling clinically often observed in "malignant infarction" was examined in ex vivo. Wister rat brain hemispheres were removed and incubated air-tightly in a deoxygenated artificial cerebrospinal fluid at 37°for 30 min. Ionic movement into the brain tissue was calculated from their concentration changes in the incubation fluid. We found a weight increase by 11.3±2.5% (p<0.01) and a decrease in Na+ from 148.0 to 139.0±8.2 mEq/l (p<0.01) and an increase in K+ from 4.3 to 11.2±1.2 mEq/l. Video tape recording revealed that the brain swelling started immediately upon the incubation, and the electronmicroscopical investigation of the swollen cortical tissue revealed that the fluid moved mainly into astroglial cells. The astroglial swelling was quite similar to that of specimen taken from clinical cases at autopsy. The driving force of the water shift can be explained by discharge of thermodynamic potential, i.e., a coupled transport of water with Na+ across the cell membrane (anomalous osmosis). The swelling was not affected by addition of aquaporin blocker, mercuric chloride. It is concluded that cerebrospinal fluid bathing the brain in situ can be the source of edema fluid for ischemic brain swelling.
KW - Anomalous osmosis
KW - Edema fluid
KW - Ischemic brain swelling
KW - Membrane depolization
UR - http://www.scopus.com/inward/record.url?scp=33644791724&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33644791724&partnerID=8YFLogxK
M3 - Article
C2 - 16543640
AN - SCOPUS:33644791724
VL - 34
SP - 223
EP - 226
JO - Clinical Hemorheology and Microcirculation
JF - Clinical Hemorheology and Microcirculation
SN - 1386-0291
IS - 1-2
ER -