Energy-dependent redox state of heme a + a3 and copper of cytochrome oxidase in perfused rat brain in situ

A study was conducted to examine the redox changes in heme a + a3 and copper in cerebral tissue as related to the mitochondrial energy state. Near-infrared spectroscopy was performed to measure the redox behavior of copper. The findings illustrate a similarity between the redox behavior of copper and the reduction of heme a3 and heme a. The results indicate that rapid reduction of heme a can precede decreases in adenosine triphosphate levels which can aid in monitoring tissue oxygenation and energy states.