[Effect of hypoxic preconditioning on the learning and memory ability and expressions of survivin and HSP-70 proteins in rats with focal cerebral ischemia/reperfusion injury].
OBJECTIVE
To study the neuroprotective effect of hypoxic preconditioning on reperfusion injury following ischemia and its molecular mechanism.


METHODS
Forty-eight rats were randomized into 3 groups, namely the sham operated group, ischemia/reperfusion (I/R) group, and I/R following hypoxic preconditioning group (HP+I/R). In the latter two groups, the rats were subjected to middle cerebral artery occlusion (MACO) for 3 h followed by reperfusion for 24 h to induce cerebral I/R injury. The learning and memory ability of the rats 24 h after reperfusion was assessed using Y-maze test. Immunohistochemistry was performed to quantify the expressions of survivin and HSP-70 proteins in the rat brain tissues.


RESULTS
The number of survivin- and HSP-70-positive cells in the brain tissues was significantly different between HP+I/R group and IR and the sham operated groups (P<0.05), and following I/R injury, the rats in HP+I/R group showed much better performance in the Y-maze test than those in I/R group.


CONCLUSIONS
Hypoxic preconditioning can protect the ischemic brain against reperfusion injury, promote recovery of the learning and memory ability and neurological functions following the injury. Up-regulation of the expressions of survivin and HSP-70 proteins might be one of the molecular mechanisms for this neuroprotective effect.
Lu
Na
N
Department of Physiology and Neurobiology, Xinxiang Medical College, Xinxiang 453003, China. luna1975lmm@sina.com
Li
Xiao-juan
XJ
Li
Cheng-zhang
CZ
Li
Dong-liang
DL
Cui
Peng-fei
PF
Hou
Yu-ning
YN
Wang
Yan-lin
YL
D000818:Animals; D001921:Brain / Q000378:metabolism; D002545:Brain Ischemia / Q000628:therapy*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D020244:Infarction, Middle Cerebral Artery; D019194:Ischemic Preconditioning; D008568:Memory; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000628:therapy*; D000077022:Survivin
C516989:Birc5 protein, rat; D018840:HSP70 Heat-Shock Proteins; D008869:Microtubule-Associated Proteins; D000077022:Survivin