The Influence Of Electroacupuncture On Expression Of Nestin,Brduå’ŒGFAP After Hypoxia-Ischemia In The Hippocampal Formation Of Neonatal Rat Brain

Objective: Hypoxic-ischemic brain damage(HIBD) plays an importment role in perinatal medicine because of the high mortality rate and neurological and intellectual impairment in the surviving infants .At present ,despite scholors have done lots of investigation in the treatment of HIBD, no effective therapeutic and neuroprotective strategies after hypoxic-ischemia (HI) have yet been available in clinic therefore , one of the most urgent tasks for obstetricians and neurologist is to develop therapeutic strategies.The primary theory conceived that the developed CNS of mammalian has no ability to generate new neurons. Evidence for neuronal self-repair following insults to the mammalian brain has been scarce until very recently. The limited ability of the mature CNS to generate new neural cells limits the self-repair capacity of the damaged brain. Stem cells are believed to provide a tool by which new cells and tissues can be made and by which damaged ones can be replaced or repaired. Do neural stem cells play an importment role in the self-repair of damage brain. Mcaky first defined neural stem cells that possess two potentials such as self-renewal and multidirectional differentiation in the mammalian brain Neural stem cells have been isolated from various regions and various development periods of the mammalian brain, recently, eperimental study indicated that electroacupuncture could high levels of DNA and RNA in neurons and increase the number of new neurons in the ischemic area of a model of middle cerebral artery occlusion .the result demonstrated that EA had the capacity to promote the recovery of brain damage fromthe molecular and cellular level. However, there were fewer reports about the treatment and the long-term effects of EA on HIBD in neonatal rats. The present study was done to observe the influence of electroacupuncturing "BaiHui" and "DaZhui" points on the neurogenesis which was reflected with immunoreactive Nesti^ Brdu and GFAP expressions in the hippocampal formation in neonatal rats after hypoxia-ischemia .so as to confirm the effects of EA on HIBD in neonatal rat, investigate the possible mechanism of neurogenesis, and provide the theoretical basis for clinical application.Methods:7-d-old Wistar rats(n= 100) weighing 12~15g were used in neurogenesis study and randomly divided into four groups. The sham-operation rats(n=25, survival n=23) were save as normal control group only received the operation without hypoxia-ischemia treatment.The animal medols (n=75, survival=66) of cerebral hypoxia-ischemia brain damage (HIBD) were prepared by left common carotied artery ligation and systemic hypoxia (8% oxygen in nitrogen) for 2h in model group(survival=20) , HIBD group(survival=22) and HIBD treated with electroacupucture group(survival=24) . Pathological changes of the hypoxia-ischemia area were observed by the TTC (2,3,5-Triphenyltetrazolium bromide) and HE staining till the rats of model group decapitated after HIBD 2 days .After 2 d of recovery, the rats of HIBD treated with electroacupucture group were treated electroacupucture ("baihui" and "dazhui"points) every day till the rats were decapitated after HIBD 22 days, the needle handles were respectively connected to stimulative machine( 16Hz, lOmV), the rats received 10 min treatment each day, each course contained 10 treatments, 2 d interval between two courses.The 42 rats (Brdu was injected into the peritoneal cavities of all rats to label the proliferating cells before decapitation) were subjected to perfusion-fixation 22 d later except the rats of model group , the left brains were regularly paraffin wax embedded, sectioned and stained by Nestle Brdu and GFAP immunohistochemical staining. The distribution and number of the postive cells were observed for quantitative and statistical analysis .Results: ?HE staining: brain edema .cerebromalacia and hemorrhage in ventricles of brain and in arachnoid were observed in the left of cerebral hemisphere of themodel group. The neuron was contract, degeneration and necrosis, the focal lysis of the brain tissue nec...