胰岛素诱导低血糖对新生大鼠海马神经干细胞增殖和分化的影响

目的探讨胰岛素诱导低血糖对新生大鼠海马神经干细胞(NSCs)增殖和分化的影响。方法新生1日龄大鼠禁食24 h后腹腔注射胰岛素50 u.kg-1,血糖值<1.0 mmol.L-1后取脑海马组织在含碱性成纤维生长因子(bFGF)、表皮生长因子(EGF)和B27的无血清培养基中进行原代和传代培养,并分别对原代和传3代的细胞进行单克隆培养及诱导分化:单克隆培养细胞行巢蛋白(Nestin)免疫细胞荧光染色;诱导分化后的细胞分别行神经元特异性烯醇化酶(NSE)、胶质纤维酸性蛋白(GFAP)免疫细胞荧光染色,计数NSE阳性细胞比例。结果原代组培养细胞与传代组和对照组原代细胞相比生长较快;单克隆培养的细胞均Nestin阳性表达,诱导分化后的细胞分别呈NSE或GFAP阳性表达;原代组的细胞诱导分化为神经元的比例明显高于传代组和对照组(P<0.05);传代组的细胞诱导分化为神经元的比例与对照组传代细胞比较无统计学意义(P>0.05)。结论低血糖能够短暂地促进新生大鼠海马神经干细胞增殖及提高向神经元分化比例。

Hypoglycemia induced by insulinum on proliferation and differentiation of neural stem cells in hippocampus of neonate tats

Objective To research the influence of hypoglycemia induced by insulinum on the proliferation and differentiation of neural stem cells（NSCs） in hippocampus of neonate rats. Methods Hypoglycemia was induced by intraperitoneal injection insulinnm 50 u · kg^-1 on neonate rats. Hippocampus of neonate rats was isolated when blood glucose was lower than 1.0 mmol · L^-1, and it was cultured using the serum-free medium containing basic fibroblast growth factor, epidermal growth factor and B27. The primary cells and the third passaged cells were monoclonal cultured and induced to differentiate by fetal bovine serum. Nestin immunofluorescence stain was used to identify NSCs after monoclone, neuron-specific enolase （NSE） and glial fibrillary acidic protein （GFAP） immunofluorescence stain were used to identify neurons and glial cells after inducing to differentiation. Then counting NSE positive cells and analyzing the data in statistics. Results The primary cells grew faster than that in the control group and the third passaged cells. The monoclonal cells all showed positive expression with Nestin. The induced differentiated cells showed positive expression with NSE or GFAP. The differentiation rate of neuron in primary group was higher than that in passaged group and control group（P 〈0.05）. There was no statistical significance in the differentiation percentage of neuron between control group and passaged group（ P 〉 0.05 ）. Conclusion Hypoglycemia may promote the proliferation of NSCs and raise the percentage of NSE positive cells differentiated from NSCs in the hippocampus of neonate rats transiently.