Establishment Of Animal Model Of Aortic Dissection And Influence Of Inflammatory Cells On Aortic Dissection

1 Objective First aim is to investigate the relationship between aortic dissection and inflammatory cells.Second aim is to explore the role of different types of inflammatory cells during the progression of AD.2 Methods Two different study systems were established by adjusting the content of β-aminopropionitrile in diet,including the gradually impairment of aorta and the aortic tear or rupture occurred suddenly within 24 hours.Nude mice（nu/nu）were used to explore the role of T lymphocyte during AD formation,LysMi^DTR mice were used to evaluate the role of monocyte/macrophage during the development of AD.H&E and orcein staing were used for histological evaluation;immunohistochemistry was used to investigate the infiltration of inflammatory cells.Immunofluorescence and immunohistochemistry were then used to investigate the mechenism why AD was regulated by monocyte/macrophage.3 Results In the development of AD,inflammatory cells including macrophages,T lymphocytes and neutrophils gradually infiltrated in the aorta,macrophages were identified as the majority among the inflammatory cells.In the acute study system,inflammatory cells aggregated rapidly with the occurrence of AD.T lymphocytes made no significance on AD formation.Based on the LysMi^DTR mice study,monocyte/macrophage depletion significantly inhibited the formation of AD;monocyte transfusion augmented the formation of AD.Macrophage colocalized with MMP-9,both depletion and transfusion of monocyte/macrophage regulated the expression level of MMP-9 in the aorta.4 Conclusions Macrophage infiltrated in the tear of aortic wall,associating with the occurrence of AD.Further more,depletion of monocyte/macrophage significantly decreased AD incidence and protected the structure of aorta.All these results indicated the privotal role of monocyte/macrophage during the formation of AD.