新生期多次吸入七氟烷后大鼠脑脊液/海马Tau蛋白的变化

Changes of Tau protein levels in rats CSF and hippocampus after multiple inhalation of sevoflurane at neonatal stage

目的探究新生期大鼠间断重复吸入七氟烷后,新生期、成年期脑脊液(CSF)、海马Tau蛋白的变化。方法健康新生SD大鼠48只,雌雄不拘,随机分为实验组(Sev组,n=24)、对照组(Con组,n=24),Sev组大鼠于出生7、14、21 d(记录为P7、P14、P21)分别予2.6%七氟烷吸入麻醉2 h。运载气体是比例为1∶1的混合气体(1L/min Air+1L/min O_2),Con组在同时间点分别吸入运载气体2 h,两组大鼠各随机取半数于新生期(P21)、成年期(P97)进行CSF及海马组织取材,分别采用ELISA及免疫组化检测CSF及海马Tau蛋白。结果新生期:大鼠CSF Tau蛋白含量两组差异不明显(P>0.05),Sev组海马Tau蛋白平均光密度均高于Con组(P<0.05);成年期:CSF Tau蛋白含量Sev组较Con组低(P<0.05),海马Tau蛋白平均光密度两组比较无统计学意义(P>0.05)。结论大鼠新生期多次吸入七氟烷后新生期Sev组海马Tau蛋白平均光密度升高、成年期Sev组CSF Tau蛋白含量降低,CSF和海马中Tau蛋白含量在不同时期变化不同步,尚不能依据CSF中Tau蛋白的变化作为反应海马Tau蛋白变化的参考指标。

Objective To investigate the changes of Tau protein levels in CSF and hippocampus of neonatal and adult rats after intermittent repeated inhalation of sevoflurane at neonatal stage. Methods 48 healthy newborn SD rats with either sex,were randomly divided into experimental group（ group Sev,n = 24） and control group（ group Con,n = 24）. The rats in the Sev group were received 2. 6% sevoflurane inhalation anesthesia for 2 h in the 7-（th）（ P7）,14-（th）（ P14）,and 21^thday（ P21）,respectively. The carrier gas consisted of oxygen and air（ 1 L/min Air ＋ 1L/Min O2）. The Con group was inhaled the carrier gas on the same way as the Sev group. Half of rats in the two groups were randomly selected in the neonatal（ P21） and adult（ P97） period to collect CSF and hippocampus.ELISA and immunohistochemistry were used to test the level of Tau protein. Results Compared to the Con group,there was no statistically significant change（ P〉0. 05） of Tau protein level in the neonatal rat CSF,and the average optical density of Tau protein in the neonatal rat hippocampus was higher（ P〈0. 05）. In the adult period,the concentration of Tau protein in CSF of the Sev group was lower than the Con group（ P〈0. 05）,however,no significant difference in the average optical density was found between the hippocampus of the two groups（ P〉0. 05）.Conclusion Repeated inhalation of sevoflurane in neonatal stage can lead to a rise in the average optical density of Tau protein in the neonatal rat hippocampus,while significantly decrease the levels of Tau protein in the adult rat CSF. The changes of Tau protein in CSF and hippocampus were not synchronous at different stages,and the change of Tau protein in CSF is not enough to be a reference index for Tau protein change in hippocampus.