Cardiac mitochondrial proteomic expression in inbred rat strains divergent in survival time after hemorrhage (STaH)

Abstract

We have previously identified inbred rat strains different in STaH (DA = FHH > BN/Mcwi). In efforts to identify cellular mechanisms and ultimately genes important to STaH, we measured cardiac mitochondrial proteins (MP) in rats from these three inbred strains (BN/Mcwi, DA, and FHH). Rats were euthanized (n = 12/strain), hearts were removed, and mitochondria were isolated. MP expression was determined using 2D DIGE‐based Quantitative Intact Proteomics. Among all strains, 1476 MP spots were detected. MP differed among strains [DA vs BN/Mcwi, n= 485 MP differed; DA vs FHH, n= 314; BN/Mcwi vs FHH, n= 430; p ≤ 0.04]. Eighty‐one MP spots were isolated and identified (IMP) using matrix‐assisted laser desorption ionization time of flight mass spectrometry. Of these, 38 distinct proteins were present and 43 IMP represented multiple posttranslational modifications of 24 of these distinct proteins. For DA rats (longest STaH), 36 IMP were increased (P ≤ .036) whereas 30 IMP were decreased (p ≤ 0.03) compared with BN/Mcwi (shortest STaH). IMP were associated with nucleic acid, lipid, and carbohydrate metabolism and with energy production. Such data indicate multiple differences exist in cardiac mitochondrial proteins among these inbred rat strains, and suggest the possibility that such protein differences might be among those cellular mechanisms influencing differences in STaH. (Funding by USAMRMC)