ACE2 Gene Overexpression Inhibited The Expression Of AT1 Receptor Of Vascular Smooth Muscle Cells In Rats

Objectives: To explore ACE2 gene transfer inhibited the expression of AT1 receptor of VSMCs in SD rats.Methods: 1.VSMCs were cultured derived-from the thoracic aorta in SD rats. 2. pc-DNA 3.1-hygro (+)-mACE2 of E. coli has been builded and Amplified in our laboratory before. 3. ACE2 gene plasmid containing pc-DNA 3.1-hygro (+)-mACE2 was transfected into VSMC using lipofection methods according to the suggestion. 4,The experiments were randomly divided into normal cells group, empty vector group, ACE2 group, Angâ…¡group, irbesartan group, ACE2 + Angâ…¡group, irbesartan + ACE2 group, irbesartan + ACE2 + Angâ…¡group, AT1 receptor mRNA and protein expression were detected by using RT-PCR and Western-Blot.Results: 1. It was found that ACE2 gene overexpression attenuated the expression of AT1 receptor mRNA in time-dependent and dose-dependent manner in VSMCs. 2. Angâ…¡induces a time-dependent and dose-dependent expression of AT1 receptor mRNA in VSMCs.3. ACE2 overexpression inhibits the expression of AT1 receptor mRNA induced by Angâ…¡in VSMCs.4.Irbesartan inhibits the expression of AT1 receptor mRNA in time-dependent and dose-dependent manner in VSMCs.5.ACE2 and irbesartan synergy inhibit the expression of AT1 receptor mRNA in VSMCs.6.Western blot confirmed that Angâ…¡increase the expression of AT1 receptor protein of aortic smooth muscle cells in rat, compared with the control group P <0.05. ACE2 inhibits the expression of AT1 receptor protein in rats vascular smooth muscle cells , compared with control group, P <0.05. ACE2 reduces the expression of AT1 receptor protein when it induced by Angâ…¡of aortic smooth muscle cells in rats, it decreased significantly compare with Angâ…¡group, P <0.05. Conclusion: Angâ…¡upregulates the expression of AT1 receptor; ACE2 reduces the expression of AT1 receptor; ACE2 and irbesartan synergy inhibits the expression of AT1 receptor mRNA in VSMCs; ACE2 inhibits the expression of AT1 receptor induced by Ang II in VSMCs; ACE2 inhibits the expression of AT1 receptor on dierctly through AT1 receptor but maybe through the decomposition of Ang II.