α-平滑肌肌动蛋白在呼吸道合胞病毒感染小鼠肺组织中的表达及意义

Expressions and significances of α-SMA in lung tissues of respiratory syncytial virus infected mice

目的:通过检测α-平滑肌肌动蛋白(α-SMA)在呼吸道合胞病毒(RSV)感染小鼠肺组织的动态表达,观察α-SMA在RSV感染后肺组织的变化,探讨α-SMA是否参与了RSV感染小鼠的发病过程。方法:随机将48只雌性BALB/c小鼠分成对照组(24只)及RSV感染组(24只),其中RSV感染组小鼠鼻腔滴入RSV100μl,对照组小鼠鼻腔滴入生理盐水100μl,分别在四个时间点(第4天、第8天、第14天、第28天)处死小鼠,留取肺组织,进行HE染色及Masson染色,免疫组化检测肺组织α-SMA的表达。结果:①Masson染色法计算气道外周胶原沉积面积百分比:对照组各时间点气道外周胶原沉积面积百分比比较无统计学差异(P>0.05);RSV感染组各时间点比较差异有统计学意义(P<0.05)。RSV感染组在感染的第4天、第8天及第14天气道外周胶原沉积面积百分比逐渐增加,与对照组相应时间点两两比较,差异有统计学意义(P<0.05),感染第28天与对照组相应时间点比较,差异无统计学意义(P>0.05)。②肺组织α-SMA表达:对照组小鼠肺组织α-SMA各时间点两两比较,表达无差异无统计学意义(P>0.05);RSV感染组小鼠肺组织α-SMA平均光密度值在第4天、第8天和第14天呈逐渐上升趋势,第14天时达高峰,至第28天下降,各时间点两两比较,差异有统计学意义(P<0.05)。RSV感染组小鼠肺组织α-SMA表达与对照组比较,第4天、第8天、第14天RSV感染组与对照组各相应时间点相比较差异有统计学意义(P<0.05),感染第28天与对照组比较差异无统计学意义(P>0.05)。结论:α-SMA参与了RSV感染小鼠气道炎症及胶原沉积过程。

Objective:To observe the changes ofα-SMA in lung tissue after Respiratory syncytial virus(RSV)infection and investigate whetherα-SMA was involved in the pathogenesis of RSV infected mice by detecting the dynamic expressions ofα-SMA in the lung tissue of RSV infected mice.Methods:Forty-eight female BALB/c mice were randomly divided into control group(n=24)and RSV infected group(n=24).The mice in the RSV infected group were dripped with 100μl RSV through the nasal cavity,while the mice in the control group were intranasally dripped with normal saline 100μl.Mice were sacrificed at four time points(day 4,8,14 and 28).Lung tissues were harvested and stained with HE and Masson.Immunohistochemistry was used to detect the expression ofα-SMA.Results:①Masson staining method to calculate the percentage of collagen deposition area around airway:There was no significant difference between each time point at the percentage of positive area of airway collagen fibers(P>0.05).Compared with each time points of RSV infected group,the difference was statistically significant(P<0.05).Compared with the control group at the corresponding time points,the percentage of positive area of airway collagen fibers gradually increased on the 4th,8th,14th day in the infected group,the difference was statistically significant(P<0.05).In the 28th day of infection,compared with the control group at the corresponding time points,there was no statistically significant difference(P>0.05).②α-SMA expression in lung tissue:In control group,there was no significant difference in each time point(P>0.05).The average optical density ofα-SMA in the mouse lung tissue of RSV infected group was gradually increased from the 4th day to the 14th day,and reached the peak on the 14th day,decreased on the 28th day.There were significant differences between the two groups at each time point(P<0.05).Compared with the control group,the expression ofα-SMA in the RSV infected group at the 4th,8th and 14th day was significant difference between the RSV infected group and the control group at the corresponding time point(P<0.05).The 28th day compared with the control group was no significant difference(P>0.05).Conclusion:α-SMA is involved in the airway inflammation and collagen deposition of RSV infection.