Potential of Nitroimidazoles as Markers of Hypoxia in Heart
It is well known that cardiac muscle has a high and continuous requirement for oxygen. Oxygen is primarily needed, i.e., over 95%, to maintain flux through mitochondrial oxidative phosphorylation for synthesis of ATP. Oxygen is delivered to the working cardiac myocytes at levels consistent with the prevailing metabolic demands established by the various ATP-dependent reactions, principally cycling of the contractile myofilaments. When oxygen delivery is diminished, for example during ischemia, electron flux within the respiratory chain is impeded by the lack of appropriate electron acceptor at the cytochrome oxidase reaction. Consequently, the concentration of reducing equivalents (NADH and FADH2) increases. This condition establishes the opportunity for these and other sources of biological reductants to interact with exogenously supplied molecules having high electron affinity.
KeywordsIodine Adduct MeOH NADH Catalase
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