The purpose of this study was to determine whether 3-HMG-Coenzyme A (HMG-CoA) reductase inhibition would attenuate the early pressure overload-induced activation of extracellular matrix genes in the left ventricle (LV) of the heart. Sprague-Dawley rats were randomized to 1 of 4 treatment groups: sham-operation+vehicle (SH-V), aortic constriction + vehicle (AC-V), AC + rosuvastatin (RSV, 2 mg/kg; AC-LO), and AC + RSV (10 mg/kg; AC-HI). Rats were injected with normal NaCl (V) or RSV once daily, beginning 1 day before surgery, and killed 1 or 3 days after surgery. Hemodynamic measurements were made in the open-chest anesthetized state. LV levels of transforming growth factor beta(1) (TGF-beta(1)), procollagen 1 (C1), and fibronectin (FN) mRNA were measured by Northern blotting. AC induced a similar to 25% increase in LV weight after 3 days that was not altered by RSV treatment. LV expression of TGF-beta(1), C1, and FN mRNA was similar to 2-fold, similar to 2.5-fold, and similar to 5-fold greater, respectively, in hearts of AC-V compared to SH-V rats 3 days post-operation, and was not significantly decreased by either dose of RSV. Inhibition of HMG-CoA reductase does not attenuate the pronounced aortic constriction-induced increases in the early expression of TGF-beta(1), C1, and FN in this model of acute pressure overload of the rat heart.