Abstract:Aim To investigate the effects of angiotensin(1-7)[Ang(1-7)] and angiotensinⅡ(AngⅡ) on scavenger receptor class B type Ⅰ(SR-BⅠ), ATP-binding cassette transporter A1(ABCA1) and cholesterol efflux in THP-1 derived foam cells. Methods Human monocytic cell line (THP-1) were induced into macrophages by 100 nmol/L phorbol myristate acetate(PMA) for 48 h, and treated with oxidized low density lipoprotein (ox-LDL) to construct the foam cells, then were randomly allocated into five groups: control group, AngⅡ group,Ang(1-7) group,Ang(1-7)+AngⅡ group and AngⅡ+Ang(1-7)+A-779 group. The mRNA and protein expression of SR-BⅠ, ABCA1 were determined by RT-PCR and Western blot, the intracellular cholesterol efflux rate was detected by liquid scintillator. Results Compared with the control group, AngⅡ decreased SR-BⅠ and ABCA1 in both protein and mRNA, and inhibited the cholesterol efflux(P<0.05). Those effects could be attenuated by cotreatment with Ang(1-7)(P<0.05). However when incubated with A-799, an inhibitor of Ang(1-7), the effects of Ang(1-7) on promoting the expression of SR-BⅠ, ABCA1 and the cholesterol efflux were significantly abolished(P<0.05). Conclusion In THP-1 derived foam cells, Ang(1-7) via its specific receptor MAS attenuates the reduction of the expression of SR-BⅠ and ABCA1 induced by AngⅡ, and increases the cholesterol efflux.