The Expression And Significance Of MicroRNA In The Lung Ischemia Reperfusion Injury (IRI) Rat Model

Objective:To investigate the relationship between microRNA and ischemia reperfusion injury in the lung tissue by measurement the expression of microRNA in the lung IRI rat model.Methods:25rat were divivded into five model group randomly, named control group(sham operation), ischemia group, IRI group (reperfusion1h,3h,6h) using improved Eppinger method establish lung IRI rat model. The expression of microRNA were detected by gene microarray in the control group, the ischemia group and the IRI group respectively. And the expression of4microRNA which changes are significance in the microarray are measured by stem-loop RT-qPCR in the five groups in order to observe the dynamic changes of microRNA in the acute injury period of ischemia reperfusion injury.Results:1. The expression of390microRNA were measured by gene microarray in the control group and ischemia group. There are4microRNA expression increased twice or more in the ischemia group, while21microRNA expression decreased twice or more in the ischemia group.2. The expression of miR-1、miR-18a、miR-31and miR-451were measured by stem-loop RT-qPCR in control group and study groups. In the control group, ischemia and reperfusion group, the expression of miR-1、miR-18a decreased after increased firstly; and the expression of miR-31was first lowered, then raised and finally decreased, the expression of miR-31was lowest in the reperfusion1hour group, and was highest in the reperfusion3hours group; the expression of miR-451decreased after increased firstly, the expression was highest in the reperfusion3hour group.Conclusions:In the acute ischemia period of lung tissue, the changes of several microRNAs expression have taken place, that argued that varieties of microRNA are involved in the ischemia reperfusion injury in the lung tissue. The expression of miRNAs(miR-1、miR-31、miR-451) related of apoptosis are up-regulated or down-regulated in IRI,and these variation suggest that the IRI mechanism, microRNA involved, are closely related to the apoptosis. The increase or decrease of miR-18a expression level related to the inhibition of angiogenesis indicated that miR-18a participated in the angiogenesis of IRI lung tissue.