ABSTRACT
AIM:To explore the effect of angiotensin II ( Ang II) on phenotypic transformation in adventitial fibroblast subpopulations isolated from rat thoracic aorta .METHODS: Vascular adventitial fibroblasts were individually expanded by the method of cloning rings .The isolated cells were identified by reverse transcription-polymerase chain reac-tion ( RT-PCR) and immunofluorescence staining .The rat vascular adventitial fibroblasts were cultured in vitro and incuba-ted with or without Ang II.Using the methods of fluorescence quantitative polymerase chain reaction (FQ-PCR), immuno-fluorescence staining and Western blot , the expression of α-smooth muscle actin (α-SMA) was detected .RESULTS:The spindle cells and round cells were isolated by the method of cloning rings .From passage 3 to passage 8,α-SMA expression was decreased in the spindle cells , and increased significantly in the round cells .Induced by Ang II , the expression of α-SMA was increased in the 2 cell subpopulations, and that in the round cells was significantly increased (P<0.01).The results of Western blot indicated that Ang II stimulated the subpopulation of the round cells to transfer to myofibroblasts . CONCLUSION:Ang II promotes the phenotypic transformation of adventitial fibroblast subpopulations , and the 2 subpop-ulations may play an important role in vascular remodeling and reparative process .