Abstract: Objective To investigate the effects of remote ischemic post-conditioning on the expression of NF200 in the brain of rats following cerebral ischemia and reperfusion in long term. Methods The focal ischemia and reperfusion rat model was made by suture method. The remote ischemic post-conditioning was performed with occluding of bilateral femoral arteries for 10 mins and reperfusion for 10 mins, repeated for 3 times at the time of reperfusion and then once a day. The rats were divided into 4 groups: the control group at 7 d after cerebral ischemia(C7, n=6), the experiment group at 7 d after cerebral ischemia(the remote ischemic post-conditioning was done everyday after cerebral ischemia, P7, n=6), the control group at 28 d after cerebral ischemia(C28, n=6), the experiment group at 28 d after cerebral ischemia(the remote ischemic post-conditioning was done everyday after cerebral ischemia, P28, n=6). The expression of NF200 protein in the brain of rats was determined by Western blotting. The immunofluorescence was used to detect the localization of NF200. Results The expression level of NF200 in P7 group increased significantly compared with that of C7 group(P<0.05); the expression level of NF200 of P28 group increased significantly compared with that of C28 group(P<0.05); The expression level of NF200 in P28 group increased significantly compared with that of P7 group(P<0.05) while the expression level of NF200 in C28 group had no significant difference compared with that of C7 group(P>0.05). Immunofluenrence staining showed that NF200 expressed both in neuron and axon. Conclusion Remote ischemic post-conditioning in long term increases the expression level of NF200 in the brain of rats, which might be the mechanism of reducing the damage of cerebral ischemia.

Key words: cerebral ischemia and reperfusion, remote ischemia post-conditioning, NF200