Protein quality control disruption and PKCβII activation during progression of heart failure in a post-myocardial infarction (MI) model of HF in rats.

<p><b>A</b>. MI-induced HF protocol (10 weeks follow up) and example of heart morphology and echo data before (left) and 4 weeks after myocardial infarction (right) in rats. <b>B</b>. Cardiac fractional shortening, <b>C</b>. Oxidized protein levels, <b>D</b>. Soluble oligomer level and <b>E</b>. Proteasomal activity during the progression of cardiac dysfunction induced by myocardial infarction. *, p<0.05 compared to week 0 (before surgery). §, p<0.05 compared to week 1 after surgery. ‡, p<0.05 compared to week 2 after surgery. <b>F</b>. Concordance between fractional shortening and proteasomal activity, and <b>G</b>. Concordance between accumulation of misfolded cardiac proteins and oxidized proteins at weeks 0, 1, 2, 4 and 10 after myocardial infarction surgery in rats, <b>H</b>. Cardiac fractional shortening, proteasomal activity, oxidized and misfolded protein levels during the progression of cardiac dysfunction induced by myocardial infarction. <b>I</b>. The levels of total PKC isozymes (white bars) and translocated active PKCs (gray bars; Triton-soluble proteins or the particulate fraction/total fraction) at 10 weeks after myocardial infarction relative to control, age-matched rats (n = 6). Total proteins and Triton-soluble proteins of the particulate fraction were normalized against GAPDH and Gαo, respectively. Representative blots are of PKCβII total level and translocation to particulate fraction. All biochemical analyses were performed in the ventricular remote area. Error bars indicate s.e.m. *, p<0.05 compared to control-TAT. <b>J</b>. PKCβII activity at 10 weeks after myocardial infarction relative to control age-matched rats (n = 3). *, p<0.05 compared to control.