【摘要】 【目的】观察核因子-κB(nuclear factor kappa B,NF-κB)在窒息新生大鼠窒息后不同时间脑组织内表达的动态变化及地塞米松(dexamethasone,DXM)早期干预的影响。【方法】出生7d新生大鼠随机分为:对照组,窒息组和DXM预处理组;制备新生大鼠窒息模型,并于窒息后1、3、5和7 d取脑组织行石蜡切片。采用免疫组织化学方法检测窒息新生鼠脑组织NF-κB p65活性表达水平及应用DXM预处理后NF-κB p65活性变化情况,用苏木精-伊红染色观察窒息后脑组织形态学变化。【结果】窒息组新生鼠脑组织NF-κB的表达较对照组显著增强(P<0.05),以5 d时升高最明显;给予DXM预处理后,NF-κB的表达减弱(P<0.05),窒息组神经元有凋亡现象,DXM预处理组凋亡神经元明显减少。【结论】窒息新生鼠脑组织NF-κB表达增加,凋亡神经元增多,窒息后5 d时NF-κB的活性达高峰;DXM可抑制窒息新生鼠NF-κB的表达,减少神经元的凋亡。DXM可能通过抑制NF-κB活性减轻窒息脑损伤。更多还原

【Abstract】 【Objectives】 To observe the activation of nuclear factor-kappa B(NF-κB)and the effect of dexamethasone on NF-κB activity in brain of newborn rats with asphyxia.The aim of the study was to explore the effect of NF-κB signal pathway in neonat with asphyxia,so as to provide the experimental base for finding clinical treatment of asphyxia,in which NF-κB was taken as the target. 【Methods】 Newborn rats(7 days old) were randomly divided into three groups:control group,asphyxia group and DXM pretreatment group.The model of asphyxia was induced in asphyxia group and DXM pretreatment group.Immunohistochemical method was used to detect the activity of NF-κB p65 in the brain of the newborn rats,and hematoxylin-eosin-stained was also performed to observe the histological evidence of asphyxia in the brain. 【Results】 The activity of NF-κB p65 was stronger in the asphyxia group than that in the control group(P<0.05),increased to the highest peak at 5 d;After DXM pretreatment NF-κB p65 activity became lower(P<0.05);The neurons had histological evidence of apoptosis in asphyxia group.Histological evidence of apoptosis was also observed in DXM pretreatment group,but less intensely. 【Conclusions】 The results suggest that NF-κB may play an important role in brain injury with asphysia.DXM have some protective effects against the brain injury and that protection seemed to be related to inhibiting augmentation of NF-κB activity.更多还原