Protein expression and the contractile function frequency response after gene transfer in human myocytes. (A) Representative bright field (left, far right panels) and fluorescence (middle panel) images of F human cardiac myocytes with AdGFP gene transfer (upper panels) compared with NT myocytes (lower panels, -AdGFP). Scale bars, 25 µm. (B) Representative Western blot analysis showing PKCα/PKCαDN, cTnI p-S44, and cTnI expression in isolated F myocytes after AdPKCα or AdPKCαDN gene transfer compared with NT myocytes. The silver-stained (Ag-stain) gel is included to show protein loading in each lane. The limited number of myocytes available for Westerns in each prep did not allow for quantitative analysis of multiple Western blots. (C) Myocyte function after gene transfer of PKCαDN into F myocytes compared with NT myocytes. Results are expressed as the percent change (%Δ) in the resting sarcomere length (SL), amplitude, shortening and relengthening rates collected at 1 versus 0.2 Hz (n = number of cells from three separate hearts in each group). Data are presented as mean ± SEM, with a Student’s unpaired t test used for statistical comparisons (*, P < 0.05 versus NT). Cells no longer contracted after gene transfer of AdPKCα into F myocytes, and therefore, this group was not included in the quantitative analysis.