Cdk5-CRMP通路在七氟醚抑制新生大鼠前额叶皮层树突发育中的作用

发布时间：2018-03-21 23:08

本文选题：七氟醚　切入点：前额叶皮层　出处：《中国病理生理杂志》2015年10期 　论文类型：期刊论文

【摘要】：目的:探究七氟醚对新生大鼠前额叶皮层(prefrontal cortex,PFC)树突发育的影响及与细胞周期依赖性蛋白激酶5(cyclin dependent kinase 5,Cdk5)-坍塌反应调节蛋白(collapsin response mediator protein,CRMP)通路的关系。方法:88只出生后7 d的SD大鼠随机分为4组,每组22只:空白对照组(Air+NS组),Cdk5抑制剂roscovitine(Ros)对照组(Air+Ros组),Sevo+NS组,Sevo+Ros组。前2组吸入空气,后2组吸入2.8%七氟醚4 h。Air+Ros组和Sevo+Ros组在麻醉前15 min经腹腔注射10 mg/kg的Cdk5抑制剂roscovitine。其余2组则在麻醉前15min经腹腔注射150μL生理盐水。麻醉结束后,每组各取5只幼鼠,取出新鲜皮质组织,Western blot检测P35、P25、Cdk5,CRMP1、2、4的蛋白表达以及CRMP2 Ser 522的磷酸化水平。剩余幼鼠继续饲养,出生后30 d每组各取6只幼鼠,取脑进行高尔基染色,制备冰冻切片,镜下观察神经元形态。其余幼鼠在出生后25~27 d进行旷场试验,31~32 d进行情景依赖性恐惧记忆检测。结果:(1)与Air+NS组比较,Sevo+NS组的P35减少了47.32%,同时P25增加了173.77%(P0.05);Sevo+Ros组的P35比Sevo+NS组增加了78.81%,其P25则减少了60.22%(P0.05)。Cdk5表达组间差异尚无统计学意义。(2)与Air+NS组比较,Sevo+NS组的总CRMP1、2和4表达分别下降了36.22%、53.74%和51.28%(P0.05),同时p-CRMP2 Ser522/CRMP2比值增加了96.20%(P0.05);Sevo+Ros组的总CRMP1和4与Sevo+NS组比较分别增加了56.95%和88.91%(P0.05),而pCRMP2 Ser522/CRMP2比值下降了43.58%(P0.05)。(3)与Air+NS组比较,Sevo+NS组的树突总长度、第二级树突长度以及60和80μm直径圆环上的交点数均显著下降(P0.01)。Sevo+Ros组的树突总长度、第二级树突长度以及60和80μm直径圆环上的交点数均比Sevo+NS组显著增加(P0.05)。(4)在恐惧记忆实验中,与Air+NS组比较,Sevo+NS组大鼠的"木僵"时间比Air+NS组减少约21%(P0.05)。Sevo+Ros组的"木僵"时间比Sevo+NS组显著增加(P0.05)。各组幼鼠在旷场实验的结果均无统计学差异。结论:七氟醚抑制了新生大鼠前额叶皮层神经元树突的正常生长发育和幼鼠学习记忆能力,而Cdk5-CRMP通路激活可能是七氟醚引起神经发育毒性的机制之一。
[Abstract]:Objective: to investigate the effect of sevoflurane on dendritic development of prefrontal cortex in neonatal rats and its relationship with the cell cycle dependent protein kinase (5(cyclin dependent kinase 5) Cdk5- collapse regulatory protein (CRMP) pathway. D SD rats were randomly divided into 4 groups. There were 22 rats in each group: control group: air NS group: roscovitine 5 inhibitor; control group: air Ros group; Sevo Ros group; the first two groups inhaled air, the first two groups inhaled air, the first two groups inhaled air, and the first two groups inhaled air. The latter two groups inhaled 2.8% sevoflurane 4 Ros group and Sevo Ros group injected roscovitine, a Cdk5 inhibitor of 10 mg/kg, 15 min before anesthesia. The other two groups were injected with 150 渭 L saline intraperitoneally before anesthesia. After anesthesia, 5 young rats were taken from each group. Fresh cortical tissues were taken out to detect the protein expression of P35, P25, Cdk5 and CRMP1, and the phosphorylation level of CRMP2 Ser 522. The remaining young rats were reared and 6 young rats were collected from each group 30 days after birth, and their brains were stained with Golgi to prepare frozen sections. The morphology of neurons was observed under microscope. The other young rats were tested for situational dependent fear memory on day 31 and 32 after birth. Results: compared with Air NS group, P35 of Sevo NS group decreased by 47.32 and P25 increased by 173.77g and 173.77g / kg respectively compared with that of Sevo Ros group. Compared with Sevo NS group, P35 increased 78.81%, while P25 decreased 60.22%(P0.05).Cdk5 expression. There was no significant difference between them.) compared with Air NS group, total CRMP1m-2 and 4 expression in Sevo NS group decreased by 36.22% and 51.28%, respectively, and p-CRMP2 Ser522/CRMP2 ratio increased by 96.20% in Sevo Ros group. 4Compared with Sevo NS group by 56.95% and 88.91%, respectively, the total dendritic length of Air NS group was decreased by 43.58% and 43.58%, respectively, compared with that of Air NS group. The length of secondary dendrites and the number of intersection points on 60 and 80 渭 m diameter rings were significantly decreased. The total length of dendrites, the length of secondary dendrites and the number of intersection points on rings of 60 and 80 渭 m diameter in the P0.01Sevo Ros group were significantly increased than those in the Sevo NS group. Compared with the Air NS group, the "stiffness" time of the Sevo NS group was significantly lower than that of the Air NS group. The "stiff" time of the 21%(P0.05).Sevo Ros group was significantly higher than that of the Sevo NS group. There was no statistical difference in the results of the open field experiment among the young rats in each group. Conclusion: sevoflurane is not significantly different in all the young rats. It inhibited the normal growth and development of dendrites of prefrontal cortex neurons and the learning and memory ability of young rats. Activation of Cdk5-CRMP pathway may be one of the mechanisms of neurotoxicity induced by sevoflurane.
【作者单位】：中山大学附属孙逸仙纪念医院麻醉科;佛山市禅城区中心医院麻醉科;
【基金】：广东省自然科学基金资助项目(No.S2013010016207) 广东省科技社会发展项目(No.2014A020212147) 广东省医学科学技术研究基金(No.A2013207)
【分类号】：R614

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