Effects Of Acupuncture Pre-conditioning On Cerebral Ischemia-reperfusion Injury In Aged Rats

Objective To investigate the effects of acupuncture pre-conditioning on apoptosis in hippocampal neurons and expression of apoptosis related genes & Inflammatory factor in serum following ischemia-reperfusion injury in aged rats.Methods Totally 120 old male wistar rats aged 19-21 months(corresponding to 60 years old human being) weighting 550-710g were randomly divided into 4 groups(n=30). Cerebral ischemic group:4-vessel-blocked was conducted for 4 minutes to establish cerebral ischemic models; Acupuncture precondition group:electro acupuncture was giving on baihui with frequency of 15 Hz, amper 2mA,30 minutes once daily for 5 days, then the rats were given 4-vessel-block for 4 minutes;sham-operation group:4 vessel were exposed; sham-acupuncture group:only electroacupuncture for 5 days without operation. The rats were killed at the end of predetermined duration of reperfusion 12h,1d,2d,3d and 7d respectively. The brain were immediately removed and hippocampal CA1 region was isolated for (1) light and electron microscopic examination of hippocampal neurons, (2) detection of apoptotic neurons(TUNEL) and (3) determination of caspase-3 protein and c-fos protein expression using SABC immuno-histochemical technique. (4) determination of nflammatory factor IL-1βand IL-6 expression in serum.Results There were apoptotic neurons in all groups. The number of apoptotic neurons and positive neurons of caspase-3 and c-fos were significantly increased and peaked at 2d after reperfusion in acupuncture precondition group and cerebral ischemic group as compared with sham-acupuncture group and sham-operation group (P<0.01). The number of apoptotic neurons and positive neurons of caspase-3 were significantly decreased and c-fos were significantly increased in acupuncture precondition groupas compared with cerebral ischemic group (P<0.01). The content of serum inflammatory factor IL-1βand IL-6 in the cerebral ischemic group and acupuncture precondition group increased obviously (P<0.01),but increased significantly in cerebral ischemic group (P<0.01)Conclusion acupuncture pre-conditioning can decrease neuron apoptosis after ischemia-reperfusion injury by regulationg and control caspase-3 protein,c-fos protein and nflammatory factor expression in aged rats.