Effect of Angiotensin-(1-7) on cell proliferation and collagen synthesis of cardiac fibroblasts induced by vasopressin

AIM: To investigate the effect of Angiotensin-(1-7) Ang-(1-7) on the cell proliferation and collagen synthesis of cardiac fibroblasts (CFs) induced by vasopressin(AVP). METHODS: CFs were isolated and cultured from neonatal SD rats. Cell number and cell cycle were evaluated by MTT assay and flow cytometry technique and Type Ⅰand Ⅲ collagen mRNA expressions in CFs were analyzed by RT-PCR. RESULTS: ① 0.1 μmol/L AVP significantly increased absorption value of CFs (0.24± 0.01) compared with that in control group (0.14± 0.01 , P0.01), and 0.001-1 μmol/L Ang-(1-7) attenuated the absorption value of AVP group in a concentration dependent manner (0.22±0.01, 0.21±0.01, 0.18±0.01 and 0.16± 0.01 , P0.01). ② Compared with those in control group (5.40± 0.67, 10.82±2.40), cells in S stage (14.00 ±0.94) and proliferation index (23.44±1.75) markedly increased in 0.1 μmol/L AVP group (P0.01). In the presence of 0.1 μmol/L Ang-(1-7), cells in S stage (8.52±0.70) and the proliferation index (16.24±2.04) were significantly lower than those in AVP group (P0.01). ③ mRNA expressions of typeⅠand Ⅲ collagens in AVP group were significantly higher than those in control group (P0.01) and in the presence of 0.001-1 μmol/L Ang-(1-7), mRNA expressions were reduced in a concentration dependent manner (P0.05). CONCLUSION: Ang-(1-7) inhibits the proliferation of CFs and the synthesis of type Ⅰand Ⅲ collagens.