[Regulative effect of electroacupuncture on aquaporin-4 in rats with focal cerebral ischemia/reperfusion].
OBJECTIVE
To study the effect of electroacupuncture (EA) on changes of aquaporin-4 (AQP4) expression in rats with cerebral ischemia/reperfusion(CI/R).


METHODS
One hundred and seventy male Sprauge-Dawley rats were randomized into control (n = 50), CI/R model (n = 60) and EA (n = 60) groups, and the later 2 groups were further divided into 6 h, 12 h, 24 h, 48 h and 72 h subgroups, with 12 cases in each. CI/R model was established by occlusion of the middle cerebral artery (MCAO). EA (3.85/6.25 Hz, 0.8 - 1.0 mA) was applied to "Shuigou" (GV 26) and "Baihui" (GV 20) for 30 min. Transcardial perfusion was conducted with normal saline + paraformaldehyde in rats of different groups for taking brain tissue samples. The degree of brain edema was detected by cresyl violet stain method, permeability of the blood-brain barrier (BBB) reflected with IgG value in brain tissue was displayed by immunohistochemistry, and AQP4 protein and mRNA expression of corpora striata (CS) were detected by using immunohistochemistry (ABC) and RT-PCR techniques respectively.


RESULTS
Twelve hours after CI/R, the hemisphere of brain began to get swelling significantly and the exosmose state of IgG became evidently; compared with the corresponding phases of model group, the swell rates in 24 h, 48 h and 72 h subgroups of EA group were significantly lower (P < 0.05, 0.01), and nearly no IgG immunoreaction positive products were found in different phases of EA group. The expression of AQP4 protein and mRNA increased significantly from 12 h and 24 h on separately in model group, while the expression in EA group was markedly weaker. The ratios of AQP4 mRNA and beta-actin mRNA of CS on the affected side of the brain from 24 h to 72 h of EA group were significantly lower than those of model group (P < 0.05, 0.01).


CONCLUSIONS
EA can reduce the degree of brain edema induced by CI/R and improve the degree of BBB injury, which may be related to its effect in down-regulating AQP4 expression.
Peng
Yong-Jun
YJ
National Key Laboratory of Medical Neurobiology, Shanghai Medical College of Fudan University, Institute of Acupuncture Research, Shanghai 200032, China.
Zhou
Fei
F
Gu
Jing
J
Yang
Ru
R
Yang
Yong-Qing
YQ
Cheng
Jie-Shi
JS
Guo
Jing-Chun
JC
D000818:Animals; D051401:Aquaporin 4 / Q000032:analysis* / Q000235:genetics; D001812:Blood-Brain Barrier; D001929:Brain Edema / Q000517:prevention & control*; D002545:Brain Ischemia / Q000378:metabolism / Q000628:therapy*; D015671:Electroacupuncture; D008297:Male; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000378:metabolism / Q000628:therapy*
D051401:Aquaporin 4; D012333:RNA, Messenger