AngII mediates stretch-induced myocardin expression in rat VSMCs. (A) AngII was measured in the culture medium by a quantitative, competitive ELISA, using a specific anti-AngII antibody. AngII levels increased significantly 6 h after 20% stretch. (B and C) Either 20% stretch or exogenous addition of AngII increased myocardin expression, and was inhibited by AngII antibodies or ARB (losartan). In this experiment, Western blots for myocardin protein in VSMCs subjected to cyclic stretch or exogenous addition of AngII in the absence or presence of inhibitors (AngII Ab or losartan) were performed. GAPDH was shown for equal amounts of protein loading in each lane. *P < 0.01 vs. control. #P < 0.01 vs. 24 h after stretch or 10 h after exogenous addition of AngII (n = 3).