猪伪狂犬病病毒感染小鼠诱导氧化应激的研究

Study on Oxidative Stress Induced by PRV Infection in Mice

旨在研究猪伪狂犬病病毒(PRV)感染小鼠后体内的氧化应激。40只昆明系小鼠设置空白对照组、PRV感染组(10^(0)TCID_(50)、10^(1)TCID_(50)、10^(2)TCID_(50)),采用肌肉注射联合滴鼻的方式感染小鼠,0.1mL/只。观察记录小鼠的临床表现,接种7d后采集小鼠脑、脾脏、肺脏和胸腺。测定免疫器官指数,PCR法检测PRV,HE染色观察小鼠脑、脾脏和肺脏组织结构病理学变化;RT-PCR法检测脾脏、肺脏氧化应激指标相关指标mRNA表达水平。结果显示,感染组小鼠脑、脾、肺均检测到PRV抗原;10^(2)TCID_(50)PRV组小鼠死亡率10%,其他组均未出现死亡;PRV感染小鼠后显著降低小鼠脾脏指数,极显著降低胸腺指数,显著或极显著上调脾和肺组织中iNOS、Nrf2及脾组织中NQO1的mRNA表达水平,极显著降低脾和肺组织中Keap1、脾组织中HO-1的mRNA表达水平;HE染色显示PRV感染小鼠的脑组织出现“血管套”现象,脾脏红髓增宽,脾小体减少和消融,红髓变宽,白髓萎缩,肺脏出现间质性肺炎。结果表明,PRV感染可成功诱导小鼠体内氧化应激,PRV剂量为10^(1)TCID_(50),0.1mL/只,该结果为进一步研究伪狂犬病病毒的致病机制和筛选抗PRV感染的有效药物奠定了基础。

The objective of this study was to study the oxidative stress in mice induced by pseudorabies virus(PRV).Forty KM mice were divided into the control group and PRV groups(10^(0)TCID_(50),10^(1)TCID_(50) and 10^(2)TCID_(50)).The animals were infected with PRV by intramuscular injection and nasal drip,O.1 mL each.The clinical manifestations of the mice were observed and recorded,and the brains,spleens,lungs,and thymus of the mice were collected at 7 d post-inoculation.Immune organ indexes were measured,and PRV antigen was detected by PCR.The histopathological changes of brains,spleens and lungs were observed by HE staining,and mRNA expression levels of oxidative stress related factors in spleen and lungs of mice were detected by RT-PCR.The results showed that the PRV antigen was found in the brains,spleens and lungs in all PRV infection groups.The mortality rate of 10^(2)TCID_(50) PRV group was 10%while there is no deaths in other groups.PRV infection significantly reduced the spleen index and extremely significantly reduced the thymus index.Moreover,PRV infection significantly or extremely significantly up-regulated the iNOS,Nrf2 and NQO1 mRNA expressions in spleen or lung tissues,and PRV infection extremely significantly down-regulated the Keapl or HO-1 mRNA expressions in spleen or lung tissues.Meanwhile,HE staining results showed that there was a phenomenon of"vascular cuff"in murine brain after PRV infection,and the red pulps of the murine spleen widened,the white pulps atrophied and the splenic corpuscles decreased.The interstitial pneumonia was developed in the murine lungs.In brief,PRV at the dose of 10^(1)TCID_(50) successfully induced oxidative stress in mice,O.1 mL each.The results provided the basis for the investigation of the pathogenesis of the PRV and screening for effective drugs against PRV infection.