电刺激大鼠小脑顶核对感觉皮层及基底节PKCγ和PKCδ表达的影响

Effect of electrical stimulation to cerebellar fastigial nucleus on the expressions of PKCγ and PKCδ in the somatosensery cortex and basal ganglia in rats

目的 观察FNS后感觉皮层及基底节PKCγ和PKCδ表达的变化 ,以探讨电刺激大鼠小脑顶核 (FNS)预置性神经保护作用的机制。方法 建立电刺激大鼠小脑顶核模型 ,分别在电刺激后即刻 ( 0h)、1、3、7、10d取感觉皮层及基底节所在脑组织 ,冰冻切片 ,进行PKCγ和PKCδ免疫组化染色 ,图像分析测定平均光密度值。并设立假刺激组及小脑顶核(DN)刺激组作为对照。结果 一侧FNS后即刻 ,对侧感觉皮层及基底节PKCγ和PKCδ表达无明显变化 (P >0 .0 5 ) ,而 1d后PKCγ和PKCδ表达显著增高 (P <0 .0 1) ;3d后 ,其表达有所降低 ,7d后其表达水平仍高于假刺激组 (P <0 .0 5 ) ,10d后降至基础水平。同侧感觉皮层及基底节在FNS后 1d ,PKCγ和PKCδ表达也有显著增高 (P <0 .0 5 ) ,但其增高水平明显低于右侧 ,3d后其表达降至基础水平。假刺激组及DN刺激后 1d ,PKCγ和PKCδ表达无明显改变。结论 FNS诱导皮层及基底节PKCγ和PKCδ表达的增高 。

Objective To investigate the mechanism of preconditioned neuroprotection of cerebellar fastigial nucleus electrical stimulation(FNS) by means of observation of the effect of FNS on the expressions of PKCγ and PKCδ in the somatosensery cortex and basal ganglia in rats. Methods FNS models in rats were established. Brain tissue containing the somatosensery cortex and basal ganglia was removed at 0 h and 1, 3, 7 and 10 d respectively after FNS and 20 μm coronal sections were obtained with a sliding cryo microtome. Immunocytochemical analysis of PKCγ and PKCδ in 2 sections from each rat was performed and the average optical density of immunostaining was quantified by computer assisted image analysis system. Sham stimulation rats and cerebral dentate nucleus (DN) stimulation rats were used as the control. Results At 0 h after FNS, no significant changes of the expressions of PKCγ and PKCδ were found in the contralateral somatosensery cortex and basal ganglia. The expressions of PKCγ and PKCδ increased significantly at 1 d and decreased at 3 d but were still higher than those in sham stimulation group at 7 d and decreased to the basal level of the control at 10 d. However, the expressions of PKCγ and PKCδ in the ipsilateral somatosensery cortex and basal ganglia were also elevated at 1 d after FNS but the increase was significantly lower than that in the contralateral ones and reached the basal level at 3 d. There was no change of PKCγ and PKCδ in sham stimulation group at 1 d after DN stimulation. Conclusion The increased expressions of PKCγ and PKCδ in the somatosensery cortex and basal ganglia induced by FNS may participate in the preconditioned neuroprotection of FNS.