Cytosolic reducing power preserves glutamate in retina.
نویسندگان
چکیده
Glutamate in neurons is an important excitatory neurotransmitter, but it also is a key metabolite. We investigated how glutamate in a neural tissue is protected from catabolism. Flux analysis using (13)C-labeled fuels revealed that retinas use activities of the malate aspartate shuttle to protect >98% of their glutamate from oxidation in mitochondria. Isolation of glutamate from the oxidative pathway relies on cytosolic NADH/NAD(+), which is influenced by extracellular glucose, lactate, and pyruvate.
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ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 110 46 شماره
صفحات -
تاریخ انتشار 2013