Anne-Marie Koop

162 12 weeks of RV pressure load induced a discrete shift towards carbohydrate metabolism Next we assessed mitochondrial respiratory capacity and expression of metabolic regulatory and transporter genes. In rats with PAB, the mitochondrial respiratory capacity using palmitoyl CoA as substrate was not significantly decreased, in both State 3 ( suppl. figure 1a ) and State 3u ( figure 2a, first graph ). The respiratory capacity using pyruvate as substrate was unchanged for State 3 ( suppl. figure 1b ). However, State 3u, representing the maximal respiratory capacity, did increase after 12 weeks of PAB as compared with control ( figure 2a, second graph ). Mitochondrial respiratory capacity in the pressure loaded right ventricle was preserved for fatty acid metabolism. However, at five and twelve weeks of pressure load a relative increase of mitochondrial respiratory capacity was found in favour of the use of carbohydrates over fatty acids.