[Protective effect of remote ischemic preconditioning against focal cerebral ischemia/reperfusion injury in rats].
OBJECTIVE
To explore the effects of remote ischemic preconditioning (RIPC) on cerebral ischemia/reperfusion (I/R) injury.


METHODS
Seventy male SD rats were randomly divided into seven groups (n=10 for each): (1) CONTROL GROUP: animals were subjected to I/R. (2)RIPC groups: RIPC was performed by 3 cycles of occlusion/reperfusion of bilateral femoral arteries for 5 minutes/5 minutes. According to the different intervals between RIPC and middle cerebral artery occlusion (MCAO), 6 RIPC subgroups were established: RIPC 30 minutes, 1, 2, 12, 24 and 48 hours subgroups, with intervals between RIPC and cerebral I/R of 30 minutes, 1, 2, 12, 24 and 48 hours respectively. The duration of MCAO was 120 minutes and reperfusion for 24 hours. The neurological dysfunction score (NDS) was evaluated at 24 hours after reperfusion. The infarction volume was then assessed with tetrazolium chloride (TTC) staining.


RESULTS
The NDSs of RIPC 1, 2 and 24 hours groups were significantly lower than that of control group (all P<0.05), while with no significant differences of RIPC 30 minutes, 12 and 48 hours groups (all P>0.05). The area percentage of infarction in RIPC 1 hour [(17.9+/-7.5)%, P=0.016], RIPC 2 hours [(18.3+/-11.2)%, P=0.019] and RIPC 24 hours [(20.2+/-11.9)%, P=0.047] groups was significantly smaller than that in control group [(30.5+/-9.8)%], while no significant differences were observed in RIPC 30 minutes, 12 and 48 hours groups (all P>0.05).


CONCLUSIONS
The RIPC the brain against focal cerebral I/R injury in rats, and the protection window is 1 to 2 hours after pretreatment and resumes after 24 hours.
Zhao
Hui
H
Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shanxi, China.
Xiong
Li-ze
LZ
Dong
Hai-long
HL
Chen
Shao-yang
SY
Lu
Zhi-hong
ZH
Sun
Yan-yuan
YY
Sun
Jing
J
Gao
Peng
P
D000818:Animals; D001921:Brain / Q000473:pathology; D004195:Disease Models, Animal; D006614:Hindlimb / Q000098:blood supply; D020244:Infarction, Middle Cerebral Artery / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D019194:Ischemic Preconditioning / Q000379:methods*; D008297:Male; D009420:Nervous System / Q000503:physiopathology; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*