Mechanical stretch reduces TGFβ induction of alpha-smooth muscle actin (ASMA) and collagen 1 expression in human cardiac fibroblasts. Human primary cardiac fibroblasts underwent either biaxial mechanical stretch for 72 h or were left un-stretched (control), in the presence of 10 ng/mL transforming growth factor beta (TGFβ). Alterations in ASMA, collagen 1, and collagen 3 gene expression were examined using quantitative real-time PCR analysis (A). Western blotting was used to quantify changes in ASMA protein expression (B). Anti-tubulin was utilized as a loading control for western blotting, allowing for semi-quantitative densitometry analysis. Bar graphs represent mean fold change ± SD. *P < 0.05, **P < 0.01, ***P < 0.001.