大鼠海马去神经支配术后急性期内神经营养因子mRNA的表达变化

Expression profile of neurotrophic factor mRNA in rat hippocampus after denervation in acute stage

目的 :观察去神经损伤后海马中胰岛素样生长因子2(insulin-like growth factor 2,IGF-2),碱性成纤维细胞生长因子2(basic fibroblastic growth factor 2,FGF-2),神经生长因子(nerve growth factor,NGF)和睫状神经营养因子(ciliary neurotrophic factor,CNTF)等神经营养因子在急性期内各时间点的基因表达变化。方法 :将28只SD大鼠随机分成双侧穹窿海马伞切割后0.5、1、2、6、12及24 h组和假手术组,在穹窿海马伞切割上述各时间点后,分别取各组大鼠海马组织,并提取总RNA,利用半定量逆转录-聚合酶链反应(reverse transcriptase polymerase chain reaction,RT-PCR)法分析切割穹窿海马伞后海马内IGF-2、FGF-2、NGF、CNTF的m RNA表达变化情况。结果:在切割大鼠穹窿海马伞后急性期的早期阶段,0.5 h组CNTF m RNA的表达量与假手术组相比明显增加(P<0.05);NGF m RNA的表达水平在12 h和24 h时与假手术组相比明显下降(P<0.05);IGF-2 m RNA的表达水平在24 h时与假手术组相比显著减少(P<0.05);FGF-2m RNA从海马伞切割后1、2、6、12和24 h均较假手术组下降(P<0.05)。结论 :切割穹窿海马伞后CNTF m RNA急性期极早期表达较假手术组上调,可能与急性期海马对应激性损伤的保护作用有关,这将为更深层次地研究海马在去神经支配损伤后神经再生与神经修复提供新的思路。

Objective： To investigate the mRNA expression of insulin-like growth factor 2（IGF-2）, basic fibroblastic growth factor 2（FGF-2）, nerve growth factor（NGF）, ciliary neurotrophic factor（CNTF） in rat hippocampus at different time points of acute stage after fimbria fornix transection. Methods： Twenty eight SD rats were randomly divided into 7 groups, 4 rats in each group. One group served as normal control and the others served as fimbria fornix transected 0.5, 1, 2, 6, 12 and 24 h group, respectively. Then hippocampus were isolated and total RNA was extracted. Semi-quantitative reverse transcriptase polymerase chain reaction（RT-PCR） method was used in detection of the expression change of IGF-2, NGF, CNTF, FGF-2 mRNA in hippocampus after fimbria fornix transection. Results： The expression level of CNTF mRNA increased in the half an hour after fimbria fornix transection, compared with the normal group（P〈0.05）; the expression level of NGF mRNA decreased at 12 h and 24 h post transection. IGF-2 began to decrease at 24 h. The expression of FGF-2 at 1, 2, 6, 12 and 24 h were lowered than that in the control group（P〈0.05）. Conclusion： After fimbria fornix transection, the expression of CNTF mRNA significantly increased, which might relate to the neurorepair or protection of hippocampus, and provid a new perspective for further study of nerve regeneration after hippocampus injury.