diaphorase

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Related to Methemoglobin reductase: methemoglobin reductase pathway

diaphorase

[dī′af·ə‚rās]
(biochemistry)
Mitochondrial flavoprotein enzymes which catalyze the reduction of dyes, such as methylene blue, by reduced pyridine nucleotides such as reduced diphosphopyridine nucleotide.
References in periodicals archive ?
Congenital methemoglobinemia may be due to defects in methemoglobin reductase. Alternatively, certain hemoglobin mutations shift the equilibrium toward the oxidized state, thereby also causing congenital methemoglobinemia.
Evidence that NADPH-dependent methemoglobin reductase and administered riboflavin protect tissues from oxidative injury.
Methemoglobinemia occurs when excessive oxidative stress produces methemoglobin at a rate that overwhelms the body's capacity to reduce it through enzyme systems (e.g., nicotinamide adenine dinucleotide [NADH] methemoglobin reductase).
The patient's NADH methemoglobin reductase activity was determined to be 15 U/g of Hb (10.1-19.4 U/g of Hb).
Infants are particularly susceptible to the condition during their first 6 months of life because they have low amounts of methemoglobin reductase, a red blood cell enzyme that converts methemoglobin back to hemoglobin.
The risk for adverse effects associated with prilocaine use is increased for infants, persons with underlying health problems (i.e., anemia or diseases affecting the respiratory or cardiovascular systems), persons with hereditary deficiencies of glucose-6-phosphate dehydrogenase and methemoglobin reductase, and persons taking other oxidant drugs (e.g., nitrite-containing medications, sulfonamides, antimalarials, or acetaminophen).
Methylene blue (MB) is frequently used as an antidote in treating methemoglobinemia [1] because it facilitates the reducing activity of the NADPH-dependent methemoglobin reductase system in erythrocytes [2].