Antibody administration and fibrosis. Animals exposed to AngII for 3 days were concurrently administered non-specific mIgG by tail vein injection. Myocardial cross-sections were stained with Sirius red to assess the AngII development of fibrosis. The percentage of collagen deposited within whole cross-sections was assessed using image analysis software (A) and qPCR was used to assess myocardial expression of Col1A1 (B). Transcript levels are reported relative to the housekeeping gene 18S. Representative images of AngII (C), and AngII + mIgG (D) are shown at 10x. *P <0.05, **P <0.01 compared to saline, +P <0.05, ++P <0.01 compared to AngII.