P-糖蛋白在大鼠癫痫持续状态表达的动态变化及其意义

Significance and dynamic expression of P-glycoprotein in status epilepticus rats

目的:研究戊四氮诱导的大鼠癫痫持续状态模型(status epilepticus,SE)中,P-糖蛋白(P-glycoprotein,P-gp)在72 h内表达的动态变化,为下一步抑制P-gp的表达选定最佳检测时间点。方法:用免疫组化、RT-q PCR和Western blot检测建模后不同时点(0、3、6、12、24、48、72 h)海马组织中P-gp表达的变化情况。结果:免疫组化结果:海马组织中P-gp蛋白在SE 24 h组的平均光密度值为0.325 1±0.008 2,比对照组增加(P<0.05),SE 48 h组的平均光密度值为0.396 3±0.016 8,显著高于对照组(P<0.01);RT-q PCR结果:MDR1a基因在SE 24 h组比对照组增加(P<0.05),SE 48 h组显著高于对照组(P<0.01);Western blot结果:P-gp蛋白在SE 48 h组比对照组增加(P<0.05)。这些结果显示,SE模型中海马组织内P-gp表达在24 h后开始升高,并在48 h达高峰。结论:SE后48 h P-gp的表达达最高峰,此时可能为减少SE后产生耐药的最佳检测时间。

Objective To investigate the dynamic expression of the drug resistance protein P-glycoprotein （P-gp） within 72 hours in the pentylenetetrazol （PTZ）-induced status epilepticus （SE） model, and to identify the optimal detection time to inhibit P-gp. Methods mRNA and protein expressions of P-gp in rats hippocampal tissue were detected by using immunohistochemistry , RT-qPCR and Western blot at different time points after modeling （0, 3, 6, 12, 24, 48, 72 h）. Results The mean density of P-gp protein in the hippocampus of status epilepticus model was 0.325 1 ± 0.008 2 at 24 h, and was 0.396 3 ± 0.016 8 at 48 h, which were consistently higher than those of the control group （P 〈 0.05, P 〈 0.01, respectively）. Results of qRT-PCR showed that MDR1a expression was significantly upregulated at 24 h and at 48 h （P 〈 0.05, P 〈 0.01, respectively）. Western blot assay revealed that P-gp protein was also significantly increased at 48 h after seizures （P 〈 0.05）. Conclusions The upregulation of P-gp after SE peaked at 48 h, which maybe the optimal detection time to detect drug resistant after SE.