Remote ischemic preconditioning protects neurocognitive function of rats following cerebral hypoperfusion.
BACKGROUND
Protection of remote ischemic preconditioning on neurocognitive function caused by bilateral common carotid artery occlusion has been investigated in rats.


METHODS
Thirty-six male Sprague-Dawley rats were divided into 3 groups - control group (Group C, n=12), bilateral carotid arteries occlusion group (Group B, n=12) and remote ischemic precondition group (Group P, n=12). In Group P, remote ischemic preconditioning (RIPC) was performed on the right femoral artery with 3 cycles (10 min) of occlusion/perfusion. After 3 cycles of preconditioning, bilateral carotid arteries were occluded immediately for 60 min. In Group B, ischemic insults were conducted without RIPC. Sham surgeries were performed in Group C. Evaluation of memory and learning capacity was performed on days 5-8 after surgery by Morris water maze testing of spatial learning capacity (n=6 for each group). Apoptosis of cells in the hippocampus region was determined by TUNEL tests and Bcl-2 at this region was determined by ELISA 24 h and 9 days after vessel occlusion (n=6 for each group).


RESULTS
Neurocognitive tests showed that latency time was significantly longer in Group B than in Group P on day 7 (p=0.016) and day 8 (p=0.036). Moreover, frequency of platform crossings was significant less in group B than in the other 2 groups on day 9. Bcl-2 level was significantly increased in the hippocampal region of rats in Group P on days 1 and 9 after vessel occlusion. TUNEL test showed that apoptosis could be observed at 24 h after occlusion in Group B, but not in Group P and Group C. No apoptosis was observed on day 9.


CONCLUSIONS
Our results suggest that RIPC can protect neurocognitive function of rats after bilateral carotid occlusions, and that Bcl-2 may play an important role in this protective effect.
Department of Anesthesiology and Intensive Care Medicine, Changhai Hospital, 2nd Military Medical University, Shanghai, P R China.
Tao
T
Xu
Zheng
Z
Gong
Wen-zhong
WZ
Zhu
Jia-feng
JF
Wang
Bo
B
Li
Feng
F
Chen
Xiao-ming
XM
Deng
D000704:Analysis of Variance; D000818:Animals; D017209:Apoptosis / Q000502:physiology; D002545:Brain Ischemia / Q000150:complications*; D002339:Carotid Arteries / Q000473:pathology; D003072:Cognition Disorders / Q000209:etiology* / Q000517:prevention & control*; D004797:Enzyme-Linked Immunosorbent Assay; D005263:Femoral Artery; D006624:Hippocampus / Q000166:cytology / Q000473:pathology*; D020287:In Situ Nick-End Labeling; D019194:Ischemic Preconditioning / Q000379:methods*; D008297:Male; D018782:Maze Learning; D051381:Rats; D017207:Rats, Sprague-Dawley