Dexamethasone treatment modulates aquaporin-4 expression after intracerebral hemorrhage in rats

• Published in: Neuroscience letters Vol. 413; no. 2; pp. 126 - 131
• Main Authors: Gu, Yan-ting, Zhang, Hua, Xue, Yi-xue
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 14.02.2007; Elsevier
• Subjects: Animals; Anti-Inflammatory Agents - pharmacology; Anti-Inflammatory Agents - therapeutic use; Aquaporin 4 - drug effects; Aquaporin 4 - genetics; Aquaporin 4 - metabolism; Aquaporin-4; Biological and medical sciences; Blood-Brain Barrier - drug effects; Blood-Brain Barrier - metabolism; Blood-Brain Barrier - physiopathology; Brain edema; Brain Edema - drug therapy; Brain Edema - etiology; Brain Edema - physiopathology; Cerebral Hemorrhage - complications; Cerebral Hemorrhage - drug therapy; Cerebral Hemorrhage - physiopathology; Dexamethasone; Dexamethasone - pharmacology; Dexamethasone - therapeutic use; Down-Regulation - drug effects; Down-Regulation - physiology; Fundamental and applied biological sciences. Psychology; Intracerebral hemmorrage; Male; Medical sciences; Neurology; Rats; Rats, Wistar; RNA, Messenger - drug effects; RNA, Messenger - metabolism; Telencephalon - blood supply; Telencephalon - drug effects; Telencephalon - physiopathology; Third Ventricle - anatomy & histology; Third Ventricle - physiology; Time Factors; Vascular diseases and vascular malformations of the nervous system; Vertebrates: nervous system and sense organs; Intracerebral hemmorrage; Brain edema; Dexamethasone; Aquaporin-4; Nervous system diseases; Rat; Rodentia; Cardiovascular disease; Cerebral disorder; Vascular disease; Vertebrata; Mammalia; Animal; Cerebral hemorrhage; Central nervous system disease; Cerebrovascular disease; Aquaporin
• ISSN: 0304-3940; 1872-7972
• DOI: 10.1016/j.neulet.2006.11.072

This study investigated whether dexamethasone (DEX) treatment could regulate the expression of aquaporin-4 (AQP4) in rats with intracerebral hemorrhage (ICH). The results demonstrated that DEX significantly reduced AQP4 mRNA level in the perihematomal area compared with control group, but it increased the level in the brain area surrounding the third ventricle at day 1 post-ICH. There was no difference in AQP4 protein levels between DEX group and control group at the two above-mentioned brain regions at day 1 after ICH. The changes in AQP4 protein induced by DEX were marked at day 3 following surgery and still lasted at day 5 post-ICH, which were accompanied by a reduction of brain edema. Our results demonstrated that the expression of AQP4 protein after ICH was region-specific, time-dependent, and also indicated that DEX-induced cerebral edema clearance was correlated with the regulation of AQP4 expression in different brain regions.