BACKGROUND:Clinical application of neural stem cells is under exploration.Currently,the indicative differentiation of neural stem cells into specific neurons to replace lost and degenerative neurons needs to solve.OBJECTIVE:To explore the effect of 83 ku protein in rat hippocempi on inducing neural stem cell differentiation into acetylcholine esterase (ACHE) positive neurons.DESIGN,TIME AND SETTING:In vitro controlled observation of cytology was performed at the Medical College of Nantong University between October 2003 and April 2008.MATERIALS:A total of 12 SD rats,of clean grade,and SD fetal rats,aged 17 days,were provided by the Experimental Animal Center of Nantong University.METHODS:The normal hippocampi and hippocampi on the 14th day after the hippocampal fimbria transection were prepared into homogenate used for 10% native-polyacrylamide gel electrophoresis,and the differential proteins of 83 ku were electroeluted.The protein concentration was adjusted to 300 mg/L.The forebrain tissues of fetal rats were harvested and neural stem cells were isolated and in vitro cultured:blank control cells were cultured in serum-free DMEM/F12 medium;83 ku normal and 83 ku transection groups were separately cultured in serum-free DMEM/F12 medium containing 10 mg/L 83 ku protein from normal and hippocampal fimbria transection rats for 12 days.MAIN OUTCOME MEASURES:AChE histochemical staining was used to detect the differentiation of neural stem cells into AChE positive neurons.RESULTS:After 12 days of culture,there was a large amount of AChE positive neurons in 83ku transection group and their bodies were very big and the processes were abundant;The AChE positive neurons in 83ku normal group were less than 83 transection group,and their bodies were small with short processes.A few of AChE positive neurons were seen in control group.There were significant differences in number of AChE positive neurons among three groups (P＜0.05).CONCLUSIONHippocampal 83 ku protein can induce neural stem cells to differentiate into AChE positive neurons.