异丙酚对大鼠脑损伤后神经细胞凋亡及脑组织 Caspase-3表达的影响

摘要

目的：探讨异丙酚对大鼠脑损伤后神经细胞凋亡及脑组织Caspase 3蛋白表达的影响，为异丙酚的临床应用提供更为重要的科学依据。方法24只雄性Wistar 大鼠随机分为假手术组、冷冻伤后0．9％氯化钠溶液组和异丙酚组。异丙酚给药量为临床麻醉相关剂量（100 mg／kg）：冷冻伤后15 min腹腔注射异丙酚50 mg／kg，0．5 h后再次追加相同剂量。采用颅骨外脑冷冻伤法，运用液氮冷冻器局部冷冻大鼠左侧顶部脑组织60 s制作冷冻伤即脑损伤模型。3组伤后24 h采用TUNEL法检测神经细胞凋亡，采用免疫组化法测定Caspase 3蛋白表达，并进行神经创伤评分。结果异丙酚组神经细胞凋亡与0．9％氯化钠溶液组比较降低（ P ＜0．05），但仍显著高于假手术组（ P ＜0．01）。脑冷冻伤后24 h，0．9％氯化钠溶液组Caspase 3蛋白阳性表达水平较假手术组明显升高（ P ＜0．01），异丙酚组脑组织Caspase 3蛋白表达水平与0．9％氯化钠溶液组比较显著降低（ P ＜0．05）。脑冷冻伤后大鼠出现神经功能障碍，伤后24 h异丙酚治疗组神经创伤评分（NSS）明显低于0．9％氯化钠溶液治疗（ P ＜0．05）。结论临床麻醉相关剂量的异丙酚可以减轻脑损伤后延迟性神经细胞凋亡、促进神经功能的恢复。%Objective To explore the effect of propofol on delayed neuronal apoptosis and Caspase 3 expression after brain injury in rats in order to provide important scientific basis for clinical application of propofol .Methods Twenty-four health male Wistar rats were randomly divided into sham -operation group , physiological saline treatment group after brain injury,propofol treatment group after brain injury .Propofol was injected intraperitoneally in a dose of 100mg/kg which was equivalent to clinical dose for general anesthesia ,in which 50mg/kg propofol was administered ip 15min after brain freezing injury,and another 50mg/kg propofol was injected at 30min after the first injection.The freezing -induced brain injury models in Wistar rats were established by freezer ( pre-cold in liquid nitrogen with the temperature at -196℃)-induced brain injury in Wistar rats on the left parietal side of skull of rat for 1 min.Apoptosis of neural cells was detected by TUNEL , and the expression of Caspase 3 protein in brain of rats was detected by immunohistochemistry , moreover , neurological severity score ( NSS) was evaluated 24 hours after brain injury .Results There was a significant difference in nerve cell apoptosis between propofol treatment group and physiological saline treatment group ( P <0.05),furthermore,the apoptosis cells in both groups were significantly more than those in sham -operation group ( P <0.01).24 hours after brain freezing injury ,the expression levels of Caspase 3 protein in physiological saline treatment group were significantly higher than those in sham -operation group ( P <0.01),however,which in propofol treatment group were significantly lower than those in physiological saline treatment group ( P <0.05).After brain freezing injury,nerve function disturbance occurred in rats ,24 hours after brain injury,the NSS in propofol treatment group were significantly lower than that in physiological saline treatment group ( P <0.05).Conclusion Propofol in clinical dose for general anesthesia can reduce delayed neuronal apoptosis ,promote recovery of nerve functionafter brain injury.