[摘要] 目的:研究凝血酶预处理(TPC)对大剂量凝血酶(TM)诱导海马神经元凋亡的影响，阐明TPC的保护作用。方法:海马神经元分别经生理盐水(Sham组)、小剂量TM(TPC组)及凝血酶受体激活肽(TRAP组)预处理48 h后再加大剂量TM作用24 h。TUNEL法及流式细胞术检测凋亡细胞数和凋亡百分率，应用免疫细胞化学方法检测神经元Bcl-2及Bax蛋白表达。结果:与Sham组比较，TPC组TUNEL阳性细胞数和凋亡百分率明显降低(P<0.01)，Bcl-2表达上调，Bax表达明显下调(P<0.01)。与Sham组比较，TRAP预处理组TUNEL阳性细胞数和凋亡百分率明显降低(P<0.01)，Bcl-2表达上调，Bax表达明显下调(P<0.01)。TRAP预处理组与TPC组相比差异无显著性(P>0.05)。结论:TPC可抑制TM导致的神经细胞凋亡，激活PAR-1，促进Bcl-2的表达和降低Bax的表达，可能是TPC抑制细胞凋亡的机制之一。

    [关键词] 凝血酶预处理；细胞凋亡；Bcl-2；Bax；蛋白酶激活受体-1

    The Effect of Thrombin Preconditioning on the Apoptosis of Hippocampal Neurons

    YANG Wen-qiong,SUN Sheng-gang,TONG E-tang.

    (Department of Neurology,Dongfeng Hospital,Yunyang Medical College,Shiyan,Hubei 442000;Department of Neurology,Union Hospital,Tongji Medical College,Huazhong University of Science and Technology,Wuhan,Hubei 430022,China)

    Abstract:Objective To investigate the effect of thrombin preconditioning(TPC)on the apoptosis of hippocampal neurons and explore the potential mechanisms. Methods Hippocampal neurons were pretreated with saline,1U/ml TM and 5μmol/L thrombin receptor activating peptides(TRAP)for 48h before exposed to 40U/ml TM,respectively.The number of apoptotic cells and apoptotic rate of neurons were measured by terminal deoxynucleotidyl transferase (TdT) mediated dUTP-biotin nick end-labeling(TUNEL)method and Flow cytometry.Bcl-2 and Bax protein expression were measured by immuocytochemical method.Results The number of apoptotic cells and apoptotic rate of neurons were decreased significantly in TPC group(P<0.01).Bcl-2 protein expression was increased, Bax protein expression was decreased significantly in TPC group(P<0.01).Compared to Sham group,the number of apoptotic cells and apoptotic rate of neurons were decreased significantly in TRAP group(P<0.01).Bcl-2 protein expression was increased,Bax protein expression was decreased significantly in TRAP group(P<0.01).There was no significant difference in TRAP group and TPC group(P>0.05).Conclusion TPC could inhibit neuron apoptosis induced by TM.The mechanism of neuroprotective effect of TPC may be through activating PAR-1,up-regulating Bcl-2 protein expression and down-regulating Bax expression. ......